Sen. Ted Cruz (R-Texas) Scott Olson/Getty Images Lt. Gen. Sean MacFarland, the commander of the US-led anti-ISIS coalition, denounced calls to "carpet bomb" ISIS during a Pentagon press briefing Monday.

Presidential candidate and Sen. Ted Cruz (R-Texas) has advocated "carpet bombing" ISIS "into oblivion," a strategy that military experts have previously pointed out is ineffective and could create mass civilian casualties.

MacFarland said that strategy is "inconsistent with our values," also citing the high risk of civilian deaths.

"At the end of the day it doesn't only matter if you win," MacFarland said. "It's how you win."

He added: "We're the United States of America. We have a set of guiding principles. Indiscriminate bombing, where we don't care if we're killing innocents or combatants, is just inconsistent with our values."

Cruz clarified his statements at the Fox News Republican debate last week. He said he would "apologize to nobody for the vigorousness with which" he would fight terrorism and destroy ISIS, also known as the Islamic State, ISIL, or Daesh.

And he said that carpet bombing isn't just "tough talk," but rather a different fundamental military strategy than that of President Barack Obama. He slammed the president for "degrading" the US military and invoked the air campaign of the Persian Gulf War as a model for what the US should do to fight ISIS in the Middle East.

But, as The Washington Post noted, many of the air attacks from that war weren't quite carpet bombing, but rather precision attacks. Carpet bombing is generally considered large-scale, unguided bombing.

Cruz has previously defended his statements about carpet bombing by saying that he would use the strategy on ISIS positions rather than the cities ISIS occupies in Iraq and Syria. But since ISIS integrates with the civilians populations it controls, it's difficult to establish enemy positions that aren't surrounded by civilians.