April 30, 2007  | By Guy Dinmore in Washington

Before its latest political crisis erupted, Turkey had been pondering a military incursion into northern Iraq to attack Kurdish rebel bases just beyond its border. But the US has begun warning Ankara to learn a lesson from what some officials in Washington are starting to call Israel's "strategic defeat" in Lebanon under similar circumstances last summer.

When a ceasefire brokered by the United Nations took effect in Lebanon last August, President George W. Bush - who had backed Israel in the month-long war against Hizbollah - declared: "Hizbollah attacked Israel. Hizbollah started the crisis, and Hizbollah suffered a defeat in this crisis".

But recently, in its effort to persuade Turkey not to attack Kurdish militants based in northern Iraq, the Bush administration has been presenting in private a different assessment of Israel's experience. In lobbying Turkey to stay its hand, US officials have described Israel's war against the Shia militant group as a "strategic defeat" that failed to achieve Israel's military goals, brought widespread international condemnation upon it, and destroyed the "myth of the invincibility of the Israeli army".

Like Israel, Turkey faces a designated terrorist group - the Kurdistan Workers party (PKK) - able to mount cross-border raids while several thousand of its fighters operate securely in territory beyond the control of a weak central Iraqi government. As a result, analysts suggest, Turkey finds itself in a similar situation now to Israel last July, except that Ankara, a long-standing Nato ally, is bereft of US support for any move against the PKK, an aspect that riles the Turkish public, politicians and military.

Ankara's military response - should it ignore US pleadings - could also be similar to Israel's, relying primarily on air power and a limited ground incursion to destroy PKK bases. Any occupation is also likely to be limited - as are Turkey's chances of a resounding success.

For the US, the main danger of a Turkish operation is that it would deal a damaging blow to the fragile Iraqi coalition government in which the Kurds play a key role, and possibly to Iraq's integrity as a single nation. General Yashar Buyukanit, chief of the Turkish general staff, said two weeks ago the military case for intervention by his forces was clear, but that it needed political approval, which had not yet been sought. A senior member of Turkey's ruling Justice and Development party told the FT that parliament would almost certainly authorise military operations if the army sought it.

Washington appears to think the threat of intervention is less serious than late last year, although "we shouldn't be cavalier about it", a senior official said.

Some senior analysts believe the Bush administration must do more to rein in its ally Massoud Barzani, the Iraqi Kurdish leader of the autonomous north who has given sanctuary to the PKK and has infuriated Turkey with his own incendiary threats.

"We have been taking it too lightly," says Lee Hamilton, adviser to the Bush administration and co-chair of the Iraq Study Group advisory panel. Turkey "won't tolerate the PKK. I think we have to pay a lot more attention to this".

Glenn Howard, president of the Jamestown Foundation, a security think-tank, says: "The whole track record of this administration is one of miscalculating Turkey." He says there isa "very strong possibility" that Turkey will mounta limited incursion into northern Iraq by the end of May.

Erol Cebeci, one of six Turkish legislators to lobby Washington last week, said that in invading Iraq the US had ignored Turkish warnings that it would open a Pandora's box of ethnic problems. "No government would tolerate this," he said of the PKK's cross-border attacks.

Sukru Elekdag, a senior member of the Turkish opposition Republican People's party, who also visited Washington, says repeated calls by Iraqi Kurds forindependence, a planned referendum, opposed by Turkey, on the future statusof the northern city of Kirkuk, which is claimedby the Kurds, and the silence of the Bush administration on supporting Turkey, have led to sus-picions of US motives in the region.

"Putting all this together we have come to the conclusion that, for the sake of relations with the Kurds, the US is willing to risk the alliance with Turkey. This is not a superficial conclusion," he says.

He indicated this was partly the result of the Turkish parliament's vote in 2003 that denied transit to US forces on their way to invade Iraq.

Copyright The Financial Times Limited 2007