2. timeline (1898-)

A good timeline here by Nelson Denis, author of War Against All Puerto Ricans. I'm including a few dates about other US territories for context. (The links to Wikipedia are to provide a quick reference, not an endorsement of all the info contained within.)

1893 - US Overthrow of the Kingdom of Hawaii
Hawaiians are made US citizens via the Hawaiian Organic Act of 1900 and Hawaii was administered as a U.S. territory until 1959, when it became the 50th state.

1898 - PR becomes a US colony following Spanish-American War
Treaty of Paris - US starts war with Spain over dubious pretext of USS Maine ship sinking in Havana Harbor, and of helping to “free” Cuba from Spain. US acquires Cuba, Puerto Rico, the Philippines, and Guam. Most of the treaty negotiations involved Cuba and repudiation of Cuba’s debt to Spain by the US. 

A People’s History of the United States - Chapter 12: THE EMPIRE AND THE PEOPLE
By Howard Zinn
“Several years before his election to the presidency, William McKinley said: "We want a foreign market for our surplus products." Senator Albert Beveridge of Indiana in early 1897 declared: "American factories are making more than the American people can use; American soil is producing more than they can consume. Fate has written our policy for us; the trade of the world must and shall be ours." 
The Department of State explained in 1898: It seems to be conceded that every year we shall be confronted with an increasing surplus of manufactured goods for sale in foreign markets if American operatives and artisans are to be kept employed the year around. The enlargement of foreign consumption of the products of our mills and workshops has, therefore, become a serious problem of statesmanship as well as of commerce.”

The Large Policy - How the Spanish-American War laid the groundwork for American empire. By Brenda Wineapple, The Nation, January 31, 2018

Fascinating arguments used by US to repudiate payment of Cuba’s debt to Spain because it was a colony:
The USA’s repudiation of the debt demanded by Spain from Cuba in 1898: What about Greece, Cyprus, Portugal, etc.? By Eric Toussaint, 8 September 2016

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1898-99 - US Military rule in PR
Commanding General Nelson A. Miles
Major General John R. Brooke
Major General Guy Vernon Henry
Major General George Whitefield Davis

 1899 - American Samoa During the Tripartite Convention, Germany and the United States partitioned the Samoan Islands into two parts. American Samoa is the only major territory of the United States in which citizenship is not granted at birth, and people born there are considered "non-citizen nationals." See Insular Cases post for more.

Puerto Rican children sent to Carlisle Indian School in Pennsylvania
“(M)any students from Puerto Rico and Cuba were also enrolled at the Carlisle and other U.S. boarding schools. It was part of a U.S. program following the Spanish American War of 1898 to "Americanize" the populations of Puerto Rico and Cuba.”

1900 - Foraker Act - US appointed civilian rule
Charles Herbert Allen May 1, 1900-September 15, 1901
William Henry Hunt September 15, 1901-July 4, 1904
Beekman Winthrop July 4, 1904-April 17, 1907
Regis Henri Post 1907-1909
George Radcliffe Colton 1909-1913

1901 - Insular Cases US Supreme Court issues a series of cases establishing a new legal distinction between incorporated and unincorporated territories. See Insular Cases post for more.

1901 - Platt Amendment
This US Congress' amendment turns Cuba into a "self-governing colony" under tight US control. “After U.S. President Theodore Roosevelt withdrew federal troops from the island in 1902, Cuba signed the treaty the next year after which Cuba executed a lease of land to the United States for a coaling and naval station at Guantánamo Bay.”

1904 - US Supreme Court Gonzales v. Williams rules Puerto Ricans are not aliens (Isabella Gonzales, Appellant, v. William Williams, United States Commissioner of Immigration at the Port of New York) 

1916 - Jones Act, the Philippines Autonomy Act passed by Congress

1917 - Jones-Shafroth Act (not to be confused with the Jones Merchant Marine Act of 1920)
Imposes US citizenship on Puerto Ricans, requires military conscription (which begins a mere 2 months later), establishes triple-tax exempt bonds (very important) to Puerto Rico “debt” situation decades later.
Puerto Ricans granted U.S. citizenship March 2, 1917 
By Andrew Glass 03/02/2008
Puerto Ricans Reflect On A Century Of (Limited) Citizenship  March 2, 2017

Also in 1917, quite a year: 
US tightens US-Mexican border:
1917 Bath Riots
The Bath Riots By David Dorado Romo
The story of the 1917 Bath Riots at the U.S.-Mexico border in Juarez, where 17-year-old Carmelita Torres led a protest of the toxic chemical “baths” required for all workers.
The Bath Riots: Indignity Along the Mexican Border January 28, 2006 by John Burnett

World War 1 - timeline
Russian Revolution(s) Feb-November 1917 collapse of Tsarist autocracy, rise of Vladimir Lenin and Bolsheviks
US Declares war on Germany April 1917
Selective Service Act of May 1917

Balfour Declaration November 1917 public statement issued by the British government during World War I announcing support for the establishment of a "national home for the Jewish people" in Palestine (Wikipedia)
100 years on: The Balfour Declaration explained Al-Jazeera
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1920 - U.S. Merchant Marine Act of 1920 (Jones Act) (also known as the Jones Act aka Cabotage Law, NOT to be confused with 1917 Jones-Shafroth Act)
American Samoa, the Northern Mariana Islands and the U.S. Virgin Islands are exempt from the Jones Act. Puerto Rico, Guam, Alaska, Hawaii, and other U.S. coastwise are covered by cabotage laws as they are considered to be inside US customs territory. The Jones Act was waived for only 10 days by DHS after Hurricane Maria, too brief of a time frame to have significantly helped Puerto Rico.

The Jones Act, the obscure 1920 shipping regulation strangling Puerto Rico, explained -- Protectionism and exploitation at its worst.
By Matthew Yglesias, Oct 9, 2017
The Jones Act, explained (and what waiving it means for Puerto Rico)
By Teresa Carey Sep 29, 2017
What is the Jones Act, and why does Puerto Rico want it gone? 
By Matt Pearce September 27, 2017
The Jones Act: The Law Strangling Puerto Rico
By Nelson A. Denis, Sept 25, 2017
La ley que está asfixiando a Puerto Rico
Por Nelson A. Denis, 27 de septiembre de 2017
Is this 1917 law suffocating Puerto Rico’s economy? PBS Aug 13, 2015 (the date in this headline is wrong)
In Defense of the Jones Act for Puerto Rico By American Maritime Partnership 2016-06-07
New York Times calls for ending the Jones Act in Puerto Rico
Opinion: Puerto Rico's economy continues to be strangled by obsolete Jones Act
By Nelson Denis Published October 25, 2016
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list of PR governors (cont.)
Arthur Yager 1913-1921
José E. Benedicto 1921-1921
Emmet Montgomery Reily July 30, 1921-March 1923
Juan Bernardo Huyke March 1923-April 1, 1923
Horace Mann Towner April 1, 1923-September 29, 1929
James R. Beverley 1929-September 9, 1929
Theodore Roosevelt Jr. September 9, 1929-January 1932
James R. Beverley 2nd Term January 1932-July 1933
Robert Hayes Gore July 1933-January 11, 1934
Benjamin Jason Horton January 11, 1934-February 5, 1934
Blanton C. Winship February 5, 1934-June 25, 1939 (gov. during Ponce Massacre)
José E. Colón June 25, 1939-September 11, 1939
William D. Leahy September 11, 1939-November 28, 1940
José Miguel Gallardo November 28, 1940-February 1941
Guy J. Swope February 1941-July 24, 1941
José Miguel Gallardo July 24, 1941-September 19, 1941
Rexford Tugwell September 19, 1941-September 2, 1946
Jesús T. Piñero September 2, 1946-January 2, 1949 (1st native PR gov)
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1939 - military occupation of Culebra begins

1941 - military occupation of Vieques begins “U.S. establishes military bases in the islands of Vieques and Culebra. The Roosevelt Roads Naval Station is one of the largest naval facilities in the world covering 32,000 acres, three harbors, and two-thirds of the island of Vieques.” See Vieques post for more info.

1948 - Puerto Rico Gag Law (Ley de la Mordaza) criminalizes anyone promoting Puerto Rico independence, owning a Puerto Rican flag or singing Puerto Rican national anthem.

Luis Muñoz Marín January 1949-January 1965 (Popular Democratic Party, Independent)

1952 - Commonwealth established
The ELA (Estado Libre Asociado or “free associated state," the literal translation in Spanish) is considered by many an elaborate ruse to get Puerto Rico off the United Nations List of Non-self-governing Territories (colonies) which requires the colonizer country to report to the UN yearly on decolonization measures. The 2 main parties are the PNP (New Progressive Party, the pro-statehood party) and the PPD (Popular Democratic Party). While not analogous to the GOP and Democratic Parties in the US, a few PNP governors have aligned GOP. Just like in the US, Puerto Rico's 2-party duopoly has resulted in narrow, unproductive, and polarizing discourse. The PNP discourse is centered around nothing can ever be solved in Puerto Rico until the political status is resolved. Keep in mind the pro-independence party numbers kept low by aggressive surveillance and targeting of independence movements.

1957-71’s (officially) - Under FBI Director J. Edgar Hoover, heavy, decades-long COINTELPRO surveillance and infiltration of Puerto Rico Independence movements on the island and in groups such as the Young Lords in NYC. Former FBI Director Louis Freeh declassified the Puerto Rico files. 
The FBI’s Dirty War Against Puerto Rico Democracy Now, May 24, 2000
The FBI’s Secret War By Branco Marcetic
Secret FBI files on 100,000 Puerto Ricans…thousands arrested…Chaos in 1950 Puerto Rico By Nelson A. Denis
New Light on Old F.B.I. Fight; Decades of Surveillance of Puerto Rican Groups By Mireya Navarro Nov. 28, 2003

1961 - Congress amended the Puerto Rico Federal Relations Act to remove the federally imposed debt limit (!)

Roberto Sánchez Vilella January 1965-January 1969 (PDP, Democrat)
Luis A. Ferré January 1969-January 1973 (New Progressive Party, Republican)
Rafael Hernández Colón January 1973-January 1977 (PDP, Democrat)
Carlos Romero Barceló January 1977-January 1985 (PNP, Democrat)
Rafael Hernández Colón January 1985-January 1993 (PDP, Democrat)
Pedro Rosselló January 1993-January 2001 (PNP, Democrat)
Sila María Calderón January 2001-January 2005 (PDP, Democrat)
Aníbal Acevedo Vilá January 2005-January 2009 (PDP, Democrat)
Luis Fortuño January 2009-January 2013 (PNP, Republican)
Alejandro García Padilla January 2013-January 2017 (PDP, Democrat)
Ricky Rosselló January 2017-present (PNP, Democrat)

1993 - NAFTA
Trade Pact Threatens Puerto Rico's Economic Rise
By Larry Rohter, Published: January 3, 1993

1996-2006 IRS SECTION 936 (Possession Tax Credit) tax incentives repeal & phase out over next 10 years
(One could argue these corporate tax incentives benefited corporations more than the local economy, but they created an artificial bubble that burst by 2006.)
Tax Policy Helped Create Puerto Rico’s Fiscal Crisis 
by Scott Greenberg/Gavin Ekins, June 30, 2015
“For over eighty years, the federal government granted various tax incentives to U.S. corporations operating in Puerto Rico, in order to spur the industrialization of the island.” 
“Ultimately, in 1996, President Clinton signed legislation that phased out section 936 over a ten year period, leaving it to be fully repealed at the beginning of 2006.” 
How dependence on corporate tax breaks corroded Puerto Rico’s economy
By Nick Brown, Dec. 20, 2016
No to the return of Section 936 by Jose Aponte-Hernandez, 09/02/16
“Even while Section 936 reduced corporations' tax bills, in 1991 alone those companies received a massive $2.8 billion tax break, the American citizens in Puerto Rico did not see a proportional benefit.” 
Puerto Rico can’t pay its debt, and the United States is partly to blame
By Rashid Marcano-Rivera July 15, 2015
“While Puerto Rico’s government should certainly share the blame, this approach ignores an important contributor to the commonwealth’s problems: the United States government’s economic and tax policies and the island’s status as a colony. Being neither an independent country nor a state constrains the Puerto Rican government’s economic development policy options.”
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1999 - February 19 - Unauthorized use of depleted uranium on Vieques by US Navy

1999 - repeal of Glass-Steagall, the Gramm–Leach–Bliley Act signed by Bill Clinton November 12, 1999

2001 - US Navy kicked out of Vieques leaving behind Vieques Atlantic Fleet Weapons Superfund site. (See Vieques for more info.)

2006 - phase out of IRS Puerto Rico Tax Incentives for Corporations Section 936 ends

2012 - During the final year of Republican Governor Luis Fortuño’s term heading the government of the colony, House Bill 3547, titled “Relocation of Investing Individuals Act,” was filed by former Speaker of the House of Representatives and current Republican candidate for Congress Jennifer Gonzalez.

In a nutshell, this bill created a tax break for American multimillionaires who have never lived on the island, to relocate in Puerto Rico where they would not have to pay taxes if they lived on the island for at least six months. Meanwhile, the rest of the Puerto Rican population, who have lived there their entire lives, would continue to pay the same high tax rate (it’s actually increasing).

The second bill filed, Senate Bill 2313, titled “Promotion of Exportation of Services Act” and authored by Republican Senate President Thomas Rivera Schatz, would extend a tax break to U.S. corporations doing business on the island, where they would only pay around four percent of corporate tax, as opposed to around 40 percent in the United States.

Both were signed into law by Governor Luis Fortuño before leaving office. They are Acts 20 and 22 of 2012.

Laws 20 and 22 that allow Americans to pay zero tax on US income if they spend at least 183 nights on the island. (!!!)

2014 - Puerto Rico enacts its own bankruptcy law or the “Ley de Quiebra Criolla” or the “Ley 71 de 2014.” or the Puerto Rico Corporation Debt Enforcement and Recovery Act. Franklin Advisers and Oppenheimer Funds immediately sued the Commonwealth of PR. The law was struck down in 2016 by the Supreme Court.

2016 - Supreme Court Rules against Puerto Rico
The death of Puerto Rico as a Commonwealth By Nelson A. Denis

April 12 - H.R. 4900 - the first version of PROMESA introduced by House Committee Chairman Rob Bishop (R-UT) and bill sponsor Rep. Sean Duffy (R-WI).

June 9 - Supreme Court rules against PR in Puerto Rico v. Sánchez Valle case.
Puerto Rico v. Sánchez Valle (Wikipedia) 
Puerto Rico not sovereign, Supreme Court says Richard Wolf, USA TODAY June 9, 2016
Puerto Rico has its own Constitution and elects its own leaders, but it remains under the thumb of Congress, the Supreme Court ruled Thursday in a 6-2 decision.
Puerto Rico’s Sovereignty Is at Stake in Supreme Court Case by AJ Vicens Jan. 12, 2016, Mother Jones
Puerto Rico v. Sánchez Valle Harvard Law Review, Nov 10, 2016

June 13 - Supreme Court rules against Puerto Rico in Puerto Rico v. Franklin California Tax-Free Trust, No. 15-233, and Acosta-Febo v. Franklin California Tax-Free Trust, No. 15-255. https://www.supremecourt.gov/opinions/15pdf/15-233_i42j.pdf
Puerto Rico Fights for Chapter 9 Bankruptcy in Supreme Court  By Mary Williams Walsh March 22, 2016, NYT
Supreme Court Rejects Puerto Rico Law in Debt Restructuring Case By Adam Liptak and Mary Williams Walsh June 13, 2016, NYT
The Supreme Court Sides With the Lenders in Puerto Rico’s Bankruptcy Case
Unable to restructure its debt, the island’s fate rests with Congress. AJ Vicens, Mother Jones, June 13, 2016
On the same day that the island enacted the Puerto Rico Corporation Debt Enforcement and Recovery Act, two mutual fund companies—Franklin Advisers and OppenheimerFunds—filed suit to block it.
Why Chapter 9 for Puerto Rico is a bad idea By Arturo C. Porzecanski, 04/08/15, The Hill
http://www.scotusblog.com/case-files/cases/puerto-rico-v-franklin-california-tax-free-trust/


June 29 - Passage of PROMESA
August 31 - Appointment of Financial Oversight Management Board

2017
Title III Debt Restructuring
May 1 - major protests in PR over austerity cuts to health, school closures, University of PR cuts
Hurricane Irma
Hurricane Maria