Turkey has in the past used the Kurdish factor as a trump card in its uneasy relations with its Iraqi, Syrian, and Iranian neighbors. At the same time, it has long considered Saddam Hussein's aggressively anti-Kurd policy as a safeguard against the subversive activities of its own separatist militants.
But the U.S. military intervention in Iraq and the ensuing political chaos have disrupted this balance.
Hasan Unal, who teaches international relations at Bilkent University in the Turkish capital, tells RFE/RL that, in Ankara's view, the situation in northern Iraq has taken an alarming twist since the March 2003 U.S.-led invasion.
"The situation is much worse, from a Turkish viewpoint, since the Americans went in," Unal says. "And in the last few months, developments have been extremely unacceptable [for Ankara]. The reasoning behind all this is that the situation in northern Iraq is leading to the establishment of some sort of a Kurdish state."
Unal implies that Prime Minister Recep Tayyip Erdogan was wrong when he assumed that by lending limited support to the U.S.-led military intervention in Iraq, Turkey would be able to influence developments south of its borders.
Of particular concern to Turkey is the strong showing that Kurdish political parties made in the 30 January Iraqi parliamentary elections.
Early returns indicate that candidates running on a joint ticket made up of northern Iraq's main two political groups -- Jalal Talabani's Patriotic Union of Kurdistan (PUK) and Mas'ud Barzani's Kurdistan Democratic Party (KDP) -- are likely to grab a large number of seats in Iraq's future National Assembly. The assembly is due to elect the next interim government and oversee drafting a new constitution.
Although the Kurds constitute Iraq's third-largest community, the intricate voting process could push them into second place in parliament, ahead of the larger Sunni minority group.
To make matters worse for Turkey, PUK leader Talabani on 3 February insisted he should be Iraq's next prime minister or president.
Of equal concern to Ankara is the fate of the oil-rich northern Iraqi city of Kirkuk and its Turkic minority. Kurds, who were expelled from Kirkuk under Saddam's policy of forced "Arabization," have in recent months returned to the city, which they want to make their regional capital.
Estimates generally put the number of Iraq's Turkic population -- known as Turkomans -- at less than 500,000. But Turkish nationalists, who claim historical rights over the former Ottoman possessions of northern Iraq, maintain the region hosts 2 million Turkomans, mainly in and around Kirkuk, Mosul, and Irbil.
Kirkuk's Arab and Turkoman parties this week accused Kurdish political groupings of fraud in a regional vote that coincided with the 30 January national polls. Both ethnic groups have also been complaining over Kurdish attempts at retaking property lost during the 1970s, when Saddam ordered the city's non-ethnic-Arab population deported.
Although Kurds flocked to Kirkuk to be employed as oil workers in the 1940s, national censuses conducted after World War II show they made up only about one-quarter of the city's population, compared to more than 50 percent in surrounding areas.
On 30 January, an informal and nonbinding referendum on independence was conducted in northern and other areas to which the Kurds lay claim, such as Kirkuk. Results show more than 80 percent of voters favor secession from Baghdad.
In Unal's words, "Turkey no longer sees the disintegration of Iraq as a remote possibility, but more and more as a nightmare scenario."
Ankara fears the creation of an economically sustainable Kurdish autonomous province in Iraq -- or even worse, an independent Kurdish state -- may prompt the officially defunct Kurdistan Workers Party (PKK) to take up arms and reignite a separatist conflict in its southeast.
In Unal's words, Turkey sees two red lines as far as its southern neighbor is concerned.
"One is Kirkuk," Unal says. "Developments around Kirkuk are very important to Turkey. Kirkuk never [was] a Kurdish city -- neither in [ancient] nor recent times. If the Kurds carry on [plans] to set up a Kurdish state of a very militant kind that would include Kirkuk, then the situation would probably concern Turkey even more. The other thing is the PKK. The Americans are, in a sense, sheltering the PKK in northern Iraq. They have given us all sorts of assurances that they would fight the PKK as soon as the first practical opportunities come up, but they haven't done so, and over the past few months they even have shown reluctance to fight the PKK. Again, this is something that is unacceptable from a Turkish viewpoint."
Following the 1999 trial of their leader, Abdullah Ocalan, PKK militants escaped to northern Iraq, where they continued to fight Turkish troops seconded by PUK and KDP peshmergas. Ankara claims some 5,000 of its Kurdish militants are hiding in the PUK-controlled mountains that separate northern Iraq from Iran and demands that the U.S.-led coalition take action against them.
But neither Washington nor its Kurdish allies have shown much willingness to move against the PKK, and consultations with U.S. Secretary of State Condoleezza Rice last week in Ankara failed to allay Turkey's concerns.
Joost Hiltermann is the Middle East project director for the International Crisis Group (ICG), a Brussels-based think tank that specializes in conflict prevention worldwide. He tells RFE/RL from his base in Jordan that none of the successors to the PKK -- such as the Kongra Gele Kurdistan, or Kurdistan People's Congress -- represents a threat to the U.S.-led coalition.
"The U.S. may eventually have to move against the PKK," Hiltermann says. "But it is obviously preoccupied with fighting an insurgency [farther south] that is much more important to it. [The PKK] is certainly not a threat to the U.S. or to anyone in northern Iraq. If anything, it is a threat to Turkish citizens and therefore to Turkey. But at the moment, I think, it is a minimal threat, a contained threat, and it is just a nagging issue that has not been resolved and ought to be resolved. It also justifies the maintenance of Turkish troops in northern Iraq. Turkey will keep troops in northern Iraq as long as the PKK is there. In a way you can understand them. But, on the other hand, it is a bit of a pretext."
Turkey's deputy army chief of staff, General Ilker Basbug, on 26 January said any unexpected developments in northern Iraq could open a rift between Ankara and Washington.
In a report released that same day, ICG analyst Hiltermann cautioned against a brewing conflict in northern Iraq that "could precipitate civil war, the breakup of the country and, in a worst-case scenario, Turkish intervention."
The Middle East expert says that although occasional Turkish threats to use force should be viewed as mainly rhetorical, there is still uncertainty over Ankara's possible responses to Kurdish claims over Kirkuk.
"There are a couple of issues that may make a [Turkish] intervention possible," Hiltermann says. "One is the existence of a strong lobby inside Turkey that would favor military intervention if the [Turkish minority] of Kirkuk were seen to be threatened. The other thing is the presence in northern Iraq of Turkish troops that could be easily deployed in Kirkuk. The question is really how much control the political leadership in Turkey has over its military forces."
But Unal of Bilkent University says Turkey has plenty of options before resorting to military force. He says, for example, Ankara could threaten to suspend its participation in the anti-Taliban campaign in Afghanistan or stop its logistical assistance to U.S. troops in Iraq in order to get its concerns heard in Washington.