Barack Obama's not even president yet, but he's already honoring his controversial campaign pledge to hold face-to-face meetings with America's worst enemies. Last week he met with George W. Bush.

Bush gave Obama a tour of some of the White House, including the Oval Office, the Lincoln Bedroom, the Nixon Incinerator, the William Henry Harrison Office Supply Closet, etc.

The pair also discussed policy. Details were scant, but one of the topics likely was the ongoing conflict between the United States and Iran.

Obama's promise to reinvigorate U.S. diplomacy by actually allowing U.S. diplomats to be diplomatic has many hoping our dangerously hateful relationship with Iran might improve.

Improvement is a reasonable expectation. Short of all-out war, relations with Iran can't get much worse. But don't expect Obama and Mahmoud Ahmadinejad to be sharing kabobs and O'Doul's at the White House anytime soon.

The deep animosity between Iran and the U.S. predates the Bush administration. Heck, it predates Obama's birth.

In 1953, when Obama was minus-8 years old, the CIA overthrew Iran's first, and last, democratic government. We were mad at Iran's government because it had the temerity to take control of the country's oil resources from the Brits -- who'd essentially been looting Iran of its oil since 1908.

Americans didn't fully realize the depth of Iranian resentment until a quarter-century later.

In 1979, the Iranian Revolution removed the country's U.S.-installed monarch. His replacement, the charismatic and supremely creepy Supreme Leader Ayatollah Khomeini, led a theocratic regime so hostile to the U.S. that it sponsored a mob raid of the American Embassy in Tehran. The mob held the embassy staff hostage for 444 days.

Since then, the U.S. supported Saddam Hussein's invasion of Iran, prompting an eight-year war that left more than 1 million people dead. Bush also lumped Iran into the so-called Axis of Evil, which implied his administration planned to overthrow Iran's government.

Iran has gone after the U.S. by proxy: by supporting enemies of Israel, like Hezbollah and Hamas, and more recently by doing its darnedest to bolster elements of the Iraqi government that are friendliest to Iran, which happen to be groups that aren't necessarily friendly to us.

The nuclear standoff between the U.S. and Iran is only the most recent chapter.

Iran is attempting to produce nuclear fuel. It says the fuel is for power plants. The U.S., European Union, and more recently the United Nations, worry the fuel is for nuclear weapons and are demanding that Iran stop.

Unfortunately, the process of making nuclear power plant fuel and nuclear weapon fuel is nearly identical. Master one, and you've essentially mastered both.

That Iran publicly tests nuclear capable ballistic missiles and seems at peace with the idea of war with Israel further makes the possibility of a nuclear-armed Iran all the more alarming to us.

What can an Obama administration do to fix the mess? First, it could try to work with Iran toward some of our mutual interests.

Both the U.S. and Iran want a stable Iraq. Their vision of Iraqi governance is somewhat different, but renewed civil war, followed by a breakup of Iraq scares the turbans off Iran's leaders. The Iranians don't want Kurdish northern Iraq to declare independence, because they worry that Kurdish parts of Iran may try to join an independent Kurdish state.

Iran and the U.S. also are united in their dislike of the Taliban in Afghanistan. Iran actually assisted the U.S. invasion in 2001. Iran craves a stable, prosperous Afghanistan on its eastern border. Afghanistan's chaos and crushing poverty has made it the world's No. 1 generator of refugees since 1980. The No. 1 destination for Afghan refugees has been Iran.

Will Obama be able to talk Iran into giving up its nuclear enrichment program? It's possible, but a lot depends on Iran.

Two things could happen to increase the chances of rapprochement (which is French for glasnost). Ahmadinejad and his hard-line faction could be replaced in March elections. And oil prices could continue to drop, giving Iran an incentive to give up its nuclear program in exchange for better economic relations with the West.

But if Iran indeed wants a nuclear weapon, Obama won't be able to stop it unilaterally.