Kurdish peshmerga forces battling the Islamic State of Iraq and Syria (ISIS) in northern Iraq say their lives depend on getting military supplies from the U.S, reports CBS News correspondent Holly Williams.

The peshmerga are foot soldiers facing off with the extremists on a 600-mile long frontline in Sinjar province. They have the best track record of defeating the militants, but they're massively out-gunned.

The Kurdish forces say they've clawed back 1,500 square miles of territory from ISIS since December, and they've done nearly all their fighting relying on small-caliber weapons.

"We have lost more than 1,000 peshmergas, and somewhere around 5,000 have been wounded," Kurdish national security adviser Masrour Barzani said.

Barzani told CBS News 70 percent of those deaths could have been prevented if the U.S. would give the peshmerga the hundreds of armored vehicles they want. So far, they've received just 25.

"Of course they all praise the peshmerga and thank us, but that is not enough, we need the equipment," Barzani said. "Let's not forget, this is a war, the enemy doesn't wait. They are not waiting for us, or for our allies to provide us with the right equipment."

The armored cars would even offer some protection against the biggest killer of the Kurdish fighters: car and roadside bombs. In a battle last month, ISIS attacked them with 14 car bombs in just one day.

"These are our heroes, and we need to protect these heroes, and I think they're the heroes of the free world, and it's the responsibility of the international community to protect them," Barzani said.

The reason the U.S. is reluctant to directly equip the peshmerga is that the Kurdish people want independence. Helping them angers the Iraqi government as well as the Turkish authorities, where there's a large Kurdish population. But that leaves the peshmerga desperately under-equipped.