There are times when Congress and much of the political class in Washington remind me of a child who can't resist sneaking a handful of cookies from the jar: They know that too much partisanship is getting them in trouble, but they can't help themselves.

Yet our country yearns for less polarization these days. How do we reduce partisanship?

The first step rests with American voters. A drumbeat of dislike for mean-spirited partisanship will get through to Congress. The rise of internet fundraising, so that less influence is wielded by groups with a cause, will also help. So would having congressional districts drawn by independent commissions. Members of Congress need to take the time to get to know one another. And they need to look deliberately for issues on which they can work together, like fixing our aging infrastructure.

In the end, though, our politicians need to understand what ordinary Americans already know: that the only way to solve our really tough problems is to work together as a nation.

Lee Hamilton is director of the Center on Congress at Indiana University. He was a member of the U.S. House of Representatives for 34 years.