Once again, George W. Bush is making a bad situation worse, defying anyone who dares to disagree with him, refusing to acknowledge fault and stubbornly dismissing any need for change. But this time the political fallout could overwhelm him and, amazingly, his potential undoing is in the national security arena he has owned since terrorists attacked on our soil Sept. 11, 2001.

The president has never been as politically isolated as he is now on the question of selling operations at U.S. seaports to a company controlled by the United Arab Emirates, perhaps his only reliable supporter on an issue that has Republicans running for the hills and Democrats rushing to the microphones. But as we saw after Hurricane Katrina, the warrantless spying debate and Vice President Dick Cheney’s accidental shooting of a friend, it is the bungling at the White House — and the president’s attention deficit — that threatens to become almost bigger than the issue at hand.

Bush’s instinct in tough times is to do what he did in his impromptu threat to veto anything Congress sends him challenging his administration’s support for selling ports to DP World. His driving style is to duct-tape his hands to the steering wheel and jam the pedal to the metal. And usually this works, because many Americans admire Bush’s trademark toughness. But this time he is defending what is widely perceived by the public as a threat to national security.

The handful of reporters on Air Force One for Bush’s Feb. 21 veto threat say they had seldom seen him so visibly angry, apparently provoked by the shock of House and Senate Republican leaders lining up against him. “If they pass a law, I’ll deal with it with a veto,” he blustered when asked how he would handle the insurrection.

Senate Majority Leader Bill Frist and House Speaker J. Dennis Hastert were wise to part ways immediately with the Bush administration’s approval of the port transaction. They understood fully the political fallout among a core of conservative voters already angry with the president for what they view as his too-permissive immigration policy. The mere appearance of foreign unfriendlies getting control of ports, no matter how unfair the image, was an obvious hot button for Republican voters upset about lax border controls and Bush’s unpopular plans to extend guest-worker status for illegal immigrants, which is expected to face a Senate vote in the next month. On the port deal, they see him as not only failing to keep the unwanted out — he’s letting them take control of vulnerable assets.

Frist and Hastert know they could lose control of Congress if national security and immigration hard-liners skip November’s midterm election balloting out of disgust. Since the Sept. 11 attacks, high turnout by these voters has fueled many election victories for Republicans, thanks to a presidential team always on the mark when it came to portraying Democrats as soft on fighting terrorists.

So why didn’t Bush and his inner circle see the sale of the terminal operations as a dangerous depressing of conservatives, and either block it or prepare a way to successfully defend it? Their political tin ear on this one recalls how they were blindsided by social conservative reaction against the Supreme Court nomination of Harriet Miers, whose thin legal credentials and insufficient record against abortion rights proved fatal to rallying the Republican base.

The White House answer to those puzzled by the flat-footed handling of the Dubai port story is almost pathetic: They say they didn’t know about it. White House spokesman Scott McClellan acknowledged last week that Bush wasn’t aware until the previous weekend that a panel headed by the Treasury Department had approved the $6.8 billion sale. And Treasury Secretary John W. Snow said he had only known about it for “three or four days.”

Even a sorry excuse like that could work if you are admitting the decision was a mistake and reversing it, or at least agreeing to study it further. In that scenario, you can scapegoat underlings to take the fall while you play the hero — even while taking a few lumps for being asleep at the switch. But it does not work in the context of Bush inflexibly defending the decision, asserting that it was fully reviewed (just not by him) and threatening Congress if anything is done about it.

In the scenario that Bush has played out, the story keeps its legs even in the unlikely event that the nation comes to see the port sale as a good thing. Questions about his character and stewardship will linger, no matter what happens.

In the wake of this debate, the popularity of Bush’s self-confidence gives way to the darker image of a strident and intolerant man who angrily defends a significant policy decision he didn’t even know about until long after it was a done deal. And that’s just what his friends are seeing in him.

Contributing Editor Craig Crawford is a news analyst for MSNBC, CNBC and “The Early Show” on CBS. He can be reached at ccrawford@cq.com.