It can be stated clearly: Tom Coburn’s greatest public service accomplishment occurred the day he retired from the U.S. Senate.

The Oklahoma Republican — for reasons that remain a mystery to many observers — continually blocked legislation aimed at helping returning veterans cope with post-traumatic stress disorder that tragically led to suicide.

Coburn is gone from the Senate. So, what did his former colleagues do? They approved a bill — in a 99-0 vote! — that seeks to improve suicide prevention efforts at the Department of Veterans Affairs. It was a stunning display of bipartisan cooperation on an issue that clearly should transcend partisan differences.

As the New York Times noted in an editorial: “The bill calls for regular independent evaluations of the V.A.’s suicide prevention and mental health programs to ensure the most effective approaches are used in its hospitals and clinics. Other provisions include a pilot program to match returning veterans with colleagues whom they can confide in about mental health concerns, and a website to make it easier for veterans and their families to find help. Another provision would help psychiatrists who work for the V.A. repay medical school debt, which could ease the chronic shortage of mental health professionals.”

And yet … Sen. Coburn — using the Senate’s procedural trickery that allows a single senator to block legislation at will — kept this legislation from getting a vote on the floor of the upper congressional chamber.

What’s more, Tom Coburn’s other profession — besides blocking legislation in the Senate — is as a physician. It’s astonishing, therefore, that he would take such an obstructionist view on this issue.

The Senate has turned an important corner and America’s veterans are better served as a result.