(CNN) Beto O'Rourke did something new for a major Democratic presidential candidate at Thursday night's debate when he said, very clearly and without any prevarication, that he'd take "weapons of war" and certain guns away from law-abiding Americans.

"Hell, yes, we're going to take your AR-15, your AK-47. We're not going to allow it to be used against our fellow Americans anymore," said O'Rourke, a former congressman from El Paso, Texas, who has re-created his presidential campaign around the issue of gun control after a mass shooting last month in his hometown.

O'Rourke is one of three Democrats , along with Sens. Kamala Harris of California and Cory Booker of New Jersey to support mandatory buybacks for certain guns. Other Democrats would make them illegal but not require them to be bought back by the government. That was O'Rourke's position, too, until the shooting in El Paso.

At the debate, O'Rourke had been asked whether he was ready to take guns away from people. He said yes, "if it's a weapon designed to kill people on a battlefield, if the high-impact, high-velocity round, when it hits your body, shreds everything inside of your body because it was designed to do that so you would bleed to death on a battlefield and not be able to get up and kill one of our soldiers."

This is something of a turning point for Democrats.