Last month former Vice President Walter Mondale turned 90, only the sixth vice president to reach that age (the others were John Adams, Levi P. Morton, John Nance Garner, Gerald Ford, and George H.W. Bush). I have missed any mention of this milestone, and think it’s worthy of some notice.

For Walter Mondale, more than anyone else, has transformed the vice presidency into a useful office. It was, notoriously, not always so: the first vice president, John Adams, lamented that it gave him almost nothing to do, with his only duty being to preside desultorily over the Senate; the second vice president, Thomas Jefferson, spent much of his four years as VP conniving to defeat Adams, the sitting president, and be elected president himself. In the early 1970s, during the vice presidency of Spiro Agnew I think (I can't find a link online), I wrote an article for the Washington Post advocating abolition of the office of vice president. I received a spirited and thoughtful dissenting letter in response from Hubert Humphrey, a politician of great energy and effectiveness, who was nevertheless notoriously frustrated in his four years in the office.

But at the time, I think I had a case. As a designated successor and not much else, many a vice president, like many a prince of Wales, became a political rival and irritant to the head of state. George II loathed his successor, Frederick Prince of Wales, and was not displeased when he predeceased him; the familial George III loathed the louche behavior of George Prince of Wales, later George IV, who connived with the king’s political opponents and attempted to oust him from power during his months of madness in 1788; Queen Victoria was dismayed by what she regarded as the dissolution of Albert Edward Prince of Wales (who jettisoned his first name when he became King Edward VII). Charles, Prince of Wales, despite his occasional eccentricities, seems to have worked out a responsible and dignified role during the 66 years he has serve as heir to the throne and awaits his 70th birthday next November.

The American vice presidency has seen similar tensions. Only twice has a vice president been elected president with the hearty blessing of the outgoing president, in the widely separated years of 1836 and 1988. Vice President Charles Dawes, after an energetic career (William McKinley’s campaign manager at age 30, first director and creator of the institutional culture of the Budget Bureau in 1921) tried to drive policy when he became vice president in 1925; President Calvin Coolidge shunted him aside. Franklin Roosevelt’s first vice president, John Nance Garner, was largely bypassed for eight years and ran against Roosevelt for the 1940 Democratic presidential nomination.

Even more damagingly, vice presidents were kept out of the loop. Harry Truman evidently spoke only twice with Franklin Roosevelt during his two months and 23 days as vice president. He didn’t know FDR was out of Washington when he was summoned to the White House from his office in the Capitol on April 12, 1945, and he had to be told about the Manhattan Project two weeks after that, at his first Cabinet meeting as president.

Vice presidents didn’t even have an office in the White House complex until even later. Even as active and commanding a presence as Nelson Rockefeller was frustrated time and again in his two years as VP.

Walter Mondale, with the indispensable and generous cooperation of President Jimmy Carter, changed that. They agreed that they would meet regularly and that the vice president would have more or less unlimited access to the president; that the vice president would have substantive responsibilities for certain public policies; that the vice president would give frank advice to the president, but would loyally support administration policy in public. There’s a certain tension in this job description, but Mondale — whose policy instincts were in some cases at odds with Carter’s, but who was temperamentally inclined toward loyalty to his fellow partisans — managed to overcome it.

It’s a precedent that has been followed, so far as I can determine, by every vice president and president since Mondale left office in January 1981. All those vice presidents — George H.W. Bush, Dan Quayle, Al Gore, Dick Cheney, Joe Biden and now Mike Pence — have been tasked with important policy duties and have made serious contributions thereon. Although they have not always agreed with their presidents’ decisions, they have maintained in loyalty in public, for institutional reasons that I think the public instinctively understands.

This is a genuine achievement. Walter Mondale transformed into a useful office a position which had frustrated some very able people from John Adams to Nelson Rockefeller. For that, I think all Americans, of whatever party, owe him a debt of gratitude. Happy birthday, Mr. Vice President.