As well as frustration at unfulfilled US promises to clamp down on the PKK in northern Iraq, Turks are angry with the US for attempting to convict Ottoman Turkey of genocide against ethnic Armenians during the First World War.

Yesterday the House of Representatives’ foreign policy committee branded the mass killings “genocide”, despite opposition from President Bush, and the issue could go to the full house for a vote.

The Armenian genocide Bill makes regular appearances in the US and Turks can do little but watch in anger and anticipation until it is eventually stopped in the interest of bilateral relations. But today Turkey has a stronger hand in play – the unexpressed threat here is: if you let us down on the Armenians, we might just ignore you and enter northern Iraq. And if we go down, this time you may come down with us.

US warnings about the possible danger to US soldiers if the Armenian Bill goes ahead and Turkish reminders about how useful a military base near the Iraqi border had been to the US operation there leave little doubt that both sides are reading the connection.

Recep Tayyip Erdogan, the Turkish Prime Minister, pointed out last night that, of the 24 military incursions Turkey’s army has mounted in pursuit of rebel Kurds in northern Iraq, none turned out to be of much lasting use. Yet, following months of passive resistance in the face of military and public calls for another one, he is on the brink of giving the order.

Turkey’s international partners, from its Nato ally, the United States, to the European Union, which it wishes to join, are strongly against the prospect of a unilateral Turkish armed forces operation into what is the only stable part of Iraq. Yet Mr Erdogan, a pro-EU and internationalist Prime Minister, has been brushing their protests aside.

As Turkey prepares to host a conference of Iraq’s neighbouring countries any such military action could undermine its leadership of the group. But the Government of former Islamists, keen to increase Turkey’s prominence in the Middle East, appears prepared to take the risk.

There is much Turkish public appetite for a strike into northern Iraq after escalating violence by the separatist Kurdistan Workers Party (PKK) culminated earlier this week in an ambush that killed 13 conscripts in an evening. Tens of thousands of people thronged the streets across the country demanding action. The military have long been complaining that the PKK’s recent resurgence has benefited from training camps in northern Iraq and US weapons obtained there.

Turkish politicians of all colours have been accusing the Government of weakness in the face of terror, and prominent media figures have been baying for PKK blood to cleanse the blood of martyrs.

Mr Erdogan, on a high after a landslide election victory in July, is under intense pressure to satisfy his public or fall back in the opinion polls during what should be a honeymoon period. His victory has also failed to completely drown out fears that his party secretly represents a threat to secularism – fears held strongly by the military, whose calls for an operation he has so far ignored.

But the timing of the current belligerent atmosphere over northern Iraq has turned the prospect of an operation into a bargaining chip in US-Turkish relations and threatens to push events beyond the range of level-headed leadership.

As Hurriyet columnist Cuneyt Ulsever points out in today’s newspaper, worsening bilateral relations and Turkish isolation in the region are feared more by the US than Turkey at a time when it is planning its retreat from Iraq and possible action against Iran.

Cengiz Candar, a veteran Middle East observer and opponent of an incursion, said: “Turkey may seek parliamentary authorisation for an incursion but then wait to see what happens with the Armenian Bill…These issues are not obviously connected and should be approached with great calm, but I am worried that events are developing in such a way that the momentum for a damaging operation is getting stronger all the time.”

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