Militarily, Turkey has NATO's biggest army after America's, and hosts a large American airbase at Incirlik.

ECONOMIST: America, Europe and Turkey

The Turks confirm that the Americans can use Incirlik to recover any pilots shot down over northern Iraq.

ECONOMIST: Turkey and Iraq

On the other hand, our big airbase in southeastern Turkey, Incirlik, is the key staging area for logistics in northern Iraq.

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Turkey has already opened its airspace to US aircraft, and transport planes have been using the base at Incirlik for refuelling.

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Turkey remains a bastion of NATO, with the biggest army after the United States and a vital American air-force base at Incirlik.

ECONOMIST: Turkish foreign policy

The more Turkey gets involved, the more comfortable the Americans feel about using Incirlik, the air base from where they, Britain and Turkey enforce a no-fly zone over northern Iraq.

ECONOMIST: Turkey and Iraq

If, for instance, they really do close down Incirlik Air Force Base, we're going to be logistically blind in the north, and it would be extremely difficult for us to re-supply and to coordinate air strikes.

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