Regardless of the substance, these purity tests executed at the barrel of a gun should make politicians of all persuasions think long and hard about putting pen to paper at their political peril.

For one, the problem with politics isn’t a lack of pledges — it’s a lack of willpower and voter accountability. Politicians make promises to voters by the mouthful while campaigning, and there’s already a handy solution in place to deal with those who ignore them: Vote them out of office. The onus is on the electorate, and pledges shouldn’t be any more powerful or binding than promises.

For another, they are, for the most part, redundant. Few Republicans would argue with the need to lower taxes or for the imperative to raise them. Further, who among them would argue with the need to cap spending levels and balance the budget, as was directed in the “Cut, Cap and Balance” pledge? Of course these are good things to do and good conservatives should do them, but should they sign their political futures over just to commit to someone’s ideological gimmick?

Some pledges seem ruthless in their consequences and, well, a little self-important. Sen. Jim DeMint promised to withhold his endorsement from any presidential candidate who failed to sign his Cut, Cap and Balance pledge.