Claire McCaskill, Missouri’s freshman senator, has been keeping her campaign promise to fight congressional earmarks, the budget process by which lawmakers funnel federal funds into pet projects back home:

Claire McCaskill campaigned against congressional earmarks last year when she ran for the Senate.

Talk about counterintuitive politics: Passing up the chance to funnel millions into your state for roads, buildings and other projects — and claim the political bragging rights — is a rare thing on Capitol Hill.

But it turns out she meant it.

Since January, the freshman Democrat from Missouri has received about 200 pleas for money from all over the state and turned down every one of them.

She thinks that using earmarks — whereby members of Congress anonymously tuck appropriations into bills without going through public hearings — is simply not the way to govern: “I honestly believe we can find a way to make serious investments without this secret, behind-closed-door process.”

It can be easy for people who applaud fiscal responsibility to lose sight of principle when it comes to the  pork projects they benefit from personally. When federal coffers are tapped for state or local spending, we don’t see the immediate cost. It’s not our money, we may tell ourselves — not most of it, anyway — so this form of government largesse seems like free cash.

But the money comes from taxpayers all the same, and when every state receives some form of funding from congressional earmarks, we all consistently pay for the frivolous spending of others. The pork windfalls we receive from earmarks are a drop in the bucket compared to what we actually pay.

Economist David D. Friedman provided an ingenious illustration for how congressional earmarks work in his book The Machinery of Freedom:

Special interest politics is a simple game. A hundred people sit in a circle, each with his pocket full of pennies. A politician walks around the outside of the circle, taking a penny from each person. No one minds; who cares about a penny? When he has gotten all the way around the circle, the politician throws fifty cents down in front of one person, who is overjoyed at the unexpected windfall. The process is repeated, ending with a different person. After a hundred rounds everyone is a hundred cents poorer, fifty cents richer, and happy.

We should congratulate McCaskill for sticking to her principles in her fight against congressional earmarks. Some Missourians might feel the pinch as their favored federal pork projects dry up, but this is a cost worth bearing to try to bring systemic reform to the appropriations process. The Springfield News-Leader agrees:

So prepare yourselves, Missourians. If McCaskill won’t participate in the traditional earmark process, that might mean the state takes a short-term financial hit. We think that will be worth it if the end game is real reform that involves Congress learning how to control its own spending.