The great Barney Frank is announcing today that he’ll retire at the end of this Congress. He’ll turn 72 in March and he’s entitled to a retirement, but he’ll be missed. His career is a reminder that even in a very partisan era, individual Members of Congress really can make a tremendous difference as legislators, and can even show that Congress — whose popularity is at record lows — can rise up to the Framers’ highest ideals in creating it.

Barney Frank is funny — really funny, not just for-Washington funny, and you’re going to read plenty of “greatest hits” type coverage of his retirement. But it’s a mistake to think of Frank as a court jester, however. He’s been a major legislator, capping his career with passage of the Dodd-Frank financial regulation package in 2010. He played more of a public opposition role during the period of GOP control of the House in 1995-2006, but before that, and since, Frank’s most important reputation has been that he’s a real legislator. He’s been both a workhorse and a showhorse.

To a large extent Frank typefies the story of the historic 111th Congress, which was one of the most productive in decades. That’s the story of veteran Democratic legislators who developed their skills before the 1994 Republican landslide finally having the chance to get big things done once Dems took control of Congress and the White House. They proved themselves very much very much up to the task. Not just Frank and Chris Dodd, but also Henry Waxman, David Price, Rosa DeLauro, Tom Harkin, Max Baucus, and many others. Remember that the stimulus in 2009 and the Affordable Care Act and Dodd-Frank in 2010 were all omnibus bills, containing lots of smaller pieces of legislation, and therefore the product of lots of Members of Congress who had been working on specific problems for years.

We’re used to thinking of everything in terms of what presidents can accomplish, and surely they are important. But Barney Frank is a reminder that Congress is the First Branch in the Constitution, and that it is made up of individual politicians, some of whom have made important and lasting contributions.

The political scientist David Mayhew wrote in “America’s Congress about these sort of Members as a particular strength of the Madisonian system. Congress isn’t only about aggregating interests; it also empowers individual legislators to really make a difference as a result of their individual actions. Indeed, these individual Members are a key source of the surprising power of the Constitutional system. We’re now going through a cycle in which there’s been a ton of turnover in Congress, with three consecutive landslide elections knocking out a lot of Members and cutting short other careers just as they were getting started, and that’s healthy, too, as is the retirement of people from Frank’s generation. But for the U.S. system to work, we’ll need some good replacements who take writing laws seriously — not just people farming out their legislating to ideological think tanks.

Barney Frank has, since 1981, been one of the very best in the House of Representatives. He’s an excellent role model for anyone, Democrat or Republican, who wants to live up to the highest of the Framers’ hopes for how the Constitution would work.