An extraordinary exclusive by Reuiters today as data on air strikes in Syria over the last few months shows that American's allies who are supposed to be helping out with air strikes against Islamic State have largely abandoned the fight leaving the US virtually alone.

As U.S. fighter jets pound Islamic State targets in Syria, Washington's coalition allies appear increasingly absent from the air war.

Although President Barack Obama's administration announced the Syrian air strikes three months ago as a joint campaign by Washington and its Arab allies, nearly 97 percent of the strikes in December have been carried out by the United States alone, according to U.S. military data provided to Reuters.

The data shows that U.S. allies have carried out just two air strikes in Syria in the first half of December, compared with 62 by the United States.

That accentuates a shift that began shortly after the start of the campaign in late September, when U.S. allies carried out 38 percent of the strikes. The percentage quickly dropped to around 8 percent in October and 9 percent in November, according to Reuters calculations based on the data.

U.S. officials are keen to prevent the coalition from fraying over concerns about the air campaign's direction. Some allies have long worried the air strikes might unintentionally bolster Syrian President Bashar al-Assad by striking a common enemy, sources said. Others in the region are also saying privately that the U.S.-led campaign against Sunni extremists needs to do more to help Sunni Muslims.

However, officials in the United States and the region insist that political tensions simmering within the coalition had nothing to do with dwindling coalition strikes.

"It's a question of targets. From a military perspective, the cooperation is extensive and deep," said a source familiar with Gulf strategy in the coalition.

Two factors are at play: a decline in the overall pace of strikes and fewer easier-to-hit fixed Islamic State targets after nearly three months of bombings, U.S. officials and Gulf sources say.

Such fixed targets were initially bombed by Bahrain, Jordan, Saudi Arabia and United Arab Emirates while the United States has from the start focused on more difficult ones, using precision-guided munitions to avoid civilian casualties.

Essentially, our Arab allies are saying they don't want to  be responsible for civilian casualties so they cherry pick targets to ensure that doesn't happen. Now that the low hanging fruit has disappeared, so has the effort of our Arab allies.

But perhaps even more problematic for our Arab allies is their insistence that the US help take down President Assad first, then go after IS. Some recent strikes by the US have relieved pressure on Assad's forces, allowing them to attack other rebel units that are supposedly friendly to the United States. The result is our confused, incompetent Syrian policy is doing little to degrade Islamic State's military while assisting President Assad in his civil war.

The Arabs are in no mood to do us any favors, so they are likely to remain on the sidelines until our Syrian policy matches up with their interests.