In Frank Bruni’s column, “The Iowa Caucuses’ Bitter Harvest,” he explains how the extremist candidacies of Santorum, Perry, and Paul are damaging both the Republican Party and the country on the whole:

As the hour of actual caucusing drew closer, Ron Paul’s campaign trumpeted his endorsement by a pastor who, as it happens, has spoken of executing homosexuals. Rick Perry pledged to devote predator drones and thousands of troops to the protection of the Mexican border, making the mission to keep every last illegal immigrant from crossing sound as urgent as rooting out terrorists in Pakistan.

And Rick Santorum, bringing his “Faith, Family and Freedom” tour to this eastern Iowa town on Thursday, promised never to be cowed by all those craven secularists who believe that a stable, healthy household needn’t be headed by a God-fearing mom and dad.

None of these three men is likely to win the Republican nomination. But before they exit stage right — stage far right, that is — they and a few of their similarly quixotic, similarly strident competitors will do no small measure of damage to the Republican Party and no great favors to the country as a whole. What happens in Iowa doesn’t stay in Iowa: it befouls Republicans’ image nationally, becomes a millstone around the eventual nominee’s neck and legitimizes debate about some matters that shouldn’t be debatable.

Why is the GOP field so beyond the beliefs of mainstream America? Because the more moderate among them (Chris Christie, Mitch Daniels, etc.) didn’t want to run against an incumbent president who won’t have to spend a penny on a primary fight and will have a war chest of hundreds of millions to spend when the battle really begins this summer. That left the field open — even after the press stopped falling for fake-outs from Sarah Palin and Donald Trump — for every level of circus performer, from Herman Cain to Newt Gingrich. Thus Mitt Romney appears to be the only reasonable person in the field, but that’s damning with faint praise.

It will also make voters about as excited in November as Democrats were in 1988 when they had to endure a carnival primary season that included ex-Klansman David Duke, soon-to-be-convicted-felon James Traficant, and sit-on-my-lap-advocate Gary Hart. In the end, they ended up with another boring Massachusetts governor who couldn’t be president — Michael Dukakis. And if you want to complete the Massachusetts can’t-win trifecta, don’t forget John Kerry, the 2004 candidate the Democrats settled for instead of womanizing John Edwards, lying Al Sharpton, and screaming Howard Dean.

Then, as now, the only voters ultra-motivated by their bland, robotic, fallback guy will be the party faithful who want the current White House resident thrown out at any expense. But more important will be whether Romney can pull in the Ron Paul activists who can’t stand him, the evangelicals who don’t accept Mormonism as a real religion, and the independents who like the health care reform law and wonder why Romney was for it before he was against it.

Maybe we should stop telling our kids that anyone can grow up to be President and start encouraging the really good ones instead.