As a result, American raids in the north have involved fighter-bombers, not B-52's, B-1's or planes like the AC-130 gunships that can attack front-line troops with far greater intensity and duration.
Somalia's information minister, Abdirahman Omar Osman, said a disproportionate number of the deaths and injuries involved fighters from Sheik Mansor's clan.
Here was the world's third biggest arms merchant reaching for a convoluted explanation to steer clear of getting involved — fighters from Iran, Iraq and Lebanon indeed disqualify Syria as a civil war zone.
The training has involved fighters from the Free Syrian Army, a loose confederation of rebel groups that the Obama administration has promised to back with expanded military assistance, said a U.S. official, who discussed the effort anonymously because he was not authorized to disclose details.
Colonel Bacon said the volcano forced cancellation of 230 training sorties in Europe, which typically involve fighter jets and refueling planes.
Marines in Falluja engaged in what was described as a heavy battle on Wednesday involving fighter jets and helicopters, in which a military spokesman said nine insurgents had been killed and three marines had been wounded.
An investigation is under way, but officials told the BBC that problems caused by ageing equipment are one of the main causes of accidents involving fighter jets.
It may be hard to believe today, but five years ago, Poland hosted the first joint NATO-Russian counter-terrorism exercise, involving fighter planes from both sides.
The Bush administration has been wary of these talks, on the grounds that they could involve fighters who have killed American troops, and in the belief that senior Taliban leaders have no interest in serious negotiations.
He said the assault would involve fighters crossing the Tigris river to the north of the city, and attacks from the east from Ajil and from northern Samarra towards the south of Tikrit.
The operation in Jarabulus, perched along Syria's border with Turkey, was a rare high-profile operation involving fighters who went through the short-lived U.S. train-and-equip program, which was supposed to be the Pentagon's main vehicle for combating the Islamic State in Syria but instead became a symbol of its failure to navigate the complexities there.
