The top U.S. general in Iraq on Monday addressed recent political rhetoric in the presidential campaign that the United States should “carpet-bomb” the Islamic State, saying that the Pentagon is bound by the laws of armed conflict and does nt indiscriminately bomb civilian areas.

“We’re the United States of America, and we have a set of guiding principles and those affect the way we as professional soldiers, airmen, sailors, Marines, conduct ourselves on the battlefield,” MacFarland said. “So indiscriminate bombing, where we don’t care if we’re killing innocents or combatants, is just inconsistent with our values. And it’s what the Russians have been accused of doing in parts of northwest Syria. Right now we have the moral high ground, and I think that’s where we need to stay.”

The comments came in response to a question from CNN’s Barbara Starr during a Pentagon news conference. The general was asked why the military isn’t engaged in “so-called carpet-bombing,” a phrase that has been used often by presidential candidate Sen. Ted Cruz (R.-Tex.).

Cruz’s use of the phrase has generated both praise and condemnation since he introduced it in December. It’s a specific term that suggests every area of a piece of land should be blanketed with bombs.

“If I am elected president, we will utterly destroy ISIS,” the Texas senator said in one instance in Iowa in December, using an acronym for the militant group. “We will utterly destroy them. We will carpet bomb them into oblivion.”

Cruz’s use of the term has evolved since then, occasionally sounding nothing like carpet-bombing at all. In a debate in December, for example, he appeared to suggest it would resemble an expanded version of the current war in Iraq, with Special Operations troops directing airstrikes with precision.

“You would carpet-bomb where ISIS is, not a city, but the location of the troops,” Cruz added in a debate later in that month. “You use air power directed — and you have embedded special forces to [direct] the air power. But the object isn’t to level a city. The object is to kill the ISIS terrorists.”

More recently, Cruz said during a presidential debate last week that he meant operations in Iraq would look more like they did during the Persian Gulf war, when the United States launched more than 1,000 airstrikes on many days. During the debate, moderator Chris Wallace of Fox News asked Cruz about his “carpet-bombing” rhetoric, and he defended the term.

Republican presidential candidate Ted Cruz doubles down on his vow to "carpet bomb" Islamic State militants at a campaign rally in Henniker, N.H. (Reuters)

“You know, you claim it is tough talk to discuss carpet bombing. It is not tough talk,” Cruz said. “It is a different, fundamental military strategy than what we’ve seen from Barack Obama.”

Cruz then criticized Obama for shrinking the military in recent years before pivoting back to what “carpet-bombing” means to him.

“You want to know what carpet bombing is? It’s what we did in the first Persian Gulf war; 1,100 air attacks a day, saturation bombing that utterly destroyed the enemy. Right now, Barack Obama is launching between 15 and 30 air attacks a day.”

Obama himself appeared to criticize Cruz’s use of the phrase during his State of the Union address, saying that “the world will look to us to help solve these problems, and our answer needs to be more than tough talk or calls to carpet bomb civilians.” Cruz countered by saying he would apologize to no one for pledging to kill Islamic State members.

Other presidential candidates have not used the words “carpet-bombing,” but some have offered similar ideas. Republican front-runner Donald Trump, for example, has said flatly that he will bomb the s—” out of the militants.