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1975:

The last U.S. troops are evacuated from Vietnam, ending more than a decade of direct involvement in that country’s civil war. U.S. forces sprayed more than 11 million gallons of the toxic herbicide known as Agent Orange over that period.

1991:

President George H.W. Bush signs the Agent Orange Act of 1991, entitling hundreds of thousands of Vietnam veterans to compensation for illnesses potentially linked to their exposure. The VA begins awarding payments to any veteran with an associated illness who earned a Vietnam Service Medal, including those who served off the coast aboard Navy ships.

2002:

A new VA interpretation of the Agent Orange Act leads the agency to amend its policy, limiting benefits to veterans who can prove they spent time inside Vietnam’s territorial boundary, where the spraying took place. Under the new rules, Navy veterans already receiving Agent Orange compensation are allowed to keep it. Any future claims from tens of thousands of other so-called Blue Water veterans who didn’t go ashore are to be denied.

2005–2009:

A group of Blue Water Navy veterans begins presenting evidence to the VA indicating that some larger Navy vessels not only served off the coast but also entered Vietnam’s territorial waters, while others frequently sent crew members ashore, presumably making them eligible for Agent Orange compensation. Sick Navy veterans who could prove they entered inland waters or went ashore begin receiving compensation on a case-by-case basis.

2010:

The VA, with help from the Blue Water Navy Vietnam Veterans Association, compiles and releases its first list of Navy ships presumed to have been exposed to Agent Orange. Veterans who served aboard the 16 ships listed – or dozens of others presumed exposed based on their hull type, such as river patrol boats – do not need to produce records to prove their vessel entered inland waters. The list is compiled based on deck logs and other records retrieved by veterans.

2010–2013:

The number of Navy ships named on the VA’s list grows from 16 to about 300 as veterans from across the country submit stacks of deck logs and other records to prove their ship either entered Vietnam’s rivers or sent crew members ashore. The National Archives and Records Administration, noticing the growing demand for Vietnam-era naval deck logs, begins digitizing some of the records and publishing them online.

2013:

At the urging of Blue Water veteran advocacy groups, the U.S. House passes a bill that would, among other things, require the Navy to search its historical records and compile a comprehensive list of ships that entered Vietnam’s inland waters or sent crew members ashore, effectively shifting that burden onto the Department of Defense. The bill dies in the U.S. Senate.

2014:

Language directing the Navy to compile a list of ship activity during the Vietnam War is inserted into the Defense Authorization Act, passing the U.S. House. The language is later stripped from the U.S. Senate version. According to veteran advocates, the Navy opposed the provision, arguing it would cost the service $5 million to compile the list.

April 2015:

The U.S. Court of Appeals for Veterans Claims directs the VA to review its policy of denying Blue Water Navy Veterans whose ships dropped anchor in Vietnam’s deep water bays and harbors. Advocates say as many as 90 percent of Blue Water veterans from the era may be covered, depending on how the VA amends its policy, because most Navy ships that came that close to shore also docked in Vietnamese harbors.

February 2016:

The VA reaffirms its policy of providing benefits only to those who served on land or in inland waters – and of requiring veterans to produce official records to prove they were there. It adds a provision making its older policy even more restrictive by excluding certain harbors that were previously included.