A word in defense of the Iowa caucuses: They do matter to the eventual outcome, and they are important for voters.

First of all, Iowa may not always pick the winner, but that is not its role. It serves three primary functions. First, it winnows the field. The field at the outset of the presidential campaign is often too large for voters to distinguish among the contestants. Only in Iowa do we get a chance to really follow candidates individually and over many months to get to know and test them.

Second, Iowa often delivers a wake-up call to the campaigns of complacent front-runners. George H.W. Bush in 1988 comes to mind. Iowa caucusgoers sent Bush a message to get out of the bubble and fight for his political life — which he did in New Hampshire. Iowa served a similar purpose for Al Gore in 2000. The campaign found itself trailing Bill Bradley in the polls and in money a few months before Iowa. Gore refocused his campaign and won the caucus handily.

Finally, the Hawkeye State can serve as a catapult for candidacies: Jimmy Carter and John McCain, for examples.

Is there a better way than Iowa to choose a president? Maybe, but it’s a little like what they say about democracy itself. For all its flaws, something better hasn’t been invented.

One final nail in the Iowa-is-irrelevant beat-down: If Mitt Romney wins Tuesday, ask him if Iowa matters.