After decades of comparing Nixon to Hitler, Reagan to Hitler and Bush to Hitler, liberals have finally decided it is wrong to make comparisons to Hitler. But the only leader to whom they have applied their newfound rule of thumb is: Iranian President Mahmoud Ahmadinejad.

While Ahmadinejad has not done anything as starkly evil as cut the capital gains tax, he does deny the Holocaust, call for the destruction of Israel, deny the existence of gays in Iran and refuses to abandon his nuclear program despite protests from the United Nations. That's the only world leader we're not allowed to compare to Hitler.

President Bush's speech at the Knesset two weeks ago was somewhat more nuanced than liberals' Hitler arguments. He did not simply jump up and down chanting: "Ahmadinejad is Hitler!" Instead, Bush condemned a policy of appeasement toward madmen, citing Neville Chamberlain's ill-fated talks with Adolf Hitler.

Suspiciously, Bush's speech was interpreted as a direct hit on B. Hussein Obama's foreign policy -- and that's according to Obama's supporters.

So to defend Obama, who -- according to his supporters -- favors appeasing madmen, liberals expanded the rule against ad Hitlerum arguments to cover any mention of the events leading to World War II. A ban on "You're like Hitler" arguments has become liberals' latest excuse to ignore history.

Unless, of course, it is liberals using historical examples to support Obama's admitted policy of appeasing dangerous lunatics. It's a strange one-sided argument when they can cite Nixon going to China and Reagan meeting with Gorbachev, but we can't cite Chamberlain meeting with Hitler.

There are reasons to meet with a tyrant, but none apply to Ahmadinejad. We're not looking for an imperfect ally against some other dictatorship, as Nixon was with China. And we aren't in a Mexican stand-off with a nuclear power, as Reagan was with the USSR. At least not yet.

Mutually Assured Destruction was bad enough with the Evil Empire, but something you definitely want to avoid with lunatics who are willing to commit suicide in order to destroy the enemies of Islam. As with the H-word, our sole objective with Ahmadinejad is to prevent him from becoming a military power.

What possible reason is there to meet with Ahmadinejad? To win a $20 bar bet as to whether or not the man actually owns a necktie?

We know his position and he knows ours. He wants nuclear arms, American troops out of the Middle East and the destruction of Israel. We don't want that. (This is assuming Mike Gravel doesn't pull off a major upset this November.) We don't need him as an ally against some other more dangerous dictator because ... well, there aren't any.

Does Obama imagine he will make demands of Ahmadinejad? Using what stick as leverage, pray tell? A U.S. boycott of the next Holocaust-denial conference in Tehran? The U.N. has already demanded that Iran give up its nuclear program. Ahmadinejad has ignored the U.N. and that's the end of it.

We always have the ability to "talk" to Ahmadinejad if we have something to say. Bush has a telephone. If Iranian crop dusters were headed toward one of our nuclear power plants, I am quite certain that Bush would be able to reach Ahmadinejad to tell him that Iran will be flattened unless the planes retreat. If his cell phone died, Bush could just post a quick warning on the Huffington Post.

Liberals view talk as an end in itself. They never think through how these talks will proceed, which is why Chamberlain ended up giving away Czechoslovakia. He didn't leave for Munich planning to do that. It is simply the inevitable result of talking with madmen without a clear and obtainable goal. Without a stick, there's only a carrot. Continued...