As President Bush commemorated Israel's 60th anniversary by attacking Barack Obama from overseas, here at home he found an all-too-frequent ally: John McCain.

When Bush accused "some" -- including Obama, Bush aides explained -- of "the false comfort of appeasement," McCain echoed this slander.

"What does he want to talk about with [Mahmoud] Ahmadinejad?" McCain asked, fumbling to link Obama to the Iranian president's hateful words. Soon, a GOP talking point was born.

Lost in the rhetoric was the question America deserves to have answered: Why should we engage with Iran?

In short, not talking to Iran has failed. Miserably.

Bush engages in self-deception arguing that not engaging Iran has worked. In fact, Iran has grown stronger: continuing to master the nuclear fuel cycle; arming militias in Iraq and Lebanon; bolstering extremist anti-Israeli proxies. It has embraced Iraqi Prime Minister Nouri al-Maliki and spends lavishly to rebuild Afghanistan, gaining influence across the region.

Instead of backing Bush's toxic rhetoric, McCain should have called George H.W. Bush's secretary of state, James Baker. After years of stonewalling, the administration grudgingly tested the Baker-Hamilton report's recommendation and opened talks with Iran -- albeit low-level dialogue restricted to the subject of Iraq. Is James Baker an appeaser, too?

While the president attacks political opponents from the Knesset, responsible members of his own administration meet face to face with Iranians. Yes, Ahmadinejad's words often are abhorrent, and often Iran has played a poisonous role in Middle East politics. But when our ambassador to Iraq meets with his Iranian counterpart, he isn't courting "the false comfort of appeasement" -- he is facing the reality that Iran exerts influence in Iraq.

That's why Defense Secretary Bob Gates and Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, have called for engaging Iran. Appeasers all? Nonsense.

Direct negotiations may be the only means short of war that can persuade Iran to forgo its nuclear capability. Given that a nuclear Iran would menace Israel, drive oil prices up past today's record highs and possibly spark a regional arms race, shouldn't we be doing all we can to avoid that conflagration?

Opponents of dialogue often quip that talking isn't a strategy. Walking away isn't a strategy, either. McCain says that "there's only one thing worse than the United States exercising the military option, that is, a nuclear-armed Iran." But for all his professed reluctance, when McCain disavows diplomacy, he is stacking the deck in favor of war.

What might we achieve by talking with Iran? Some say our engagement to date has not been productive -- but a less half-hearted and less conditional approach might well break the stalemate. We won't know until we try.

Dialogue helps us isolate Ahmadinejad rather than empowering him to isolate us. More important, even if we fail to reach an agreement, engaging Iran will spark three conversations likely to strengthen our position.

The first is between our leaders and Iran's. From nonproliferation to counterterrorism, frankly, Iran won't care for much of what we have to say -- but at the right moment, it is not unreasonable to think Tehran would cut a deal in exchange for economic incentives, energy assistance, diplomatic normalization or a non-invasion guarantee.

Second is the conversation America's president should be having with the Iranian people. We should seize the chance to tell some of the region's most pro-American people how their own president has isolated them, denying their great culture its place in the world and the region a constructive dialogue.

There's a reason the late Tom Lantos, Congress's only Holocaust survivor and a formidable diplomat, applied for a visa to enter Iran every year for the last decade of his life. What better way to puncture the petty lies of a demagogue than to force him to confront a man who has lived the very history he denies and trivializes?

Some have asserted that meeting with Iran's leaders would legitimize Ahmadinejad, who is neither Iran's supreme leader nor someone whom Obama specifically promised to meet. Curiously, many critics then hype Ahmadinejad as a threat of historic proportions, thereby granting the stature they seek to deny. Iranian elections in mid-2009 could yield a less objectionable president; engaging Iran makes that more likely.

The third conversation is with the world. By engaging Iran, we reclaim the moral high ground -- no small feat. If Iran refuses to budge, we have new leverage to expose it as a threat whose bad intentions cannot be explained away.

Those who say they take no option off the table should not put America in a straitjacket by denouncing diplomacy.

As Iran's centrifuges churn out enriched uranium, we're asking the wrong question. Instead of wondering why Barack Obama wants to talk with Iran, we should ask: "What are George Bush and John McCain waiting for?" 

This essay is also featured in the Washington Post.