The Editorial Board

USA TODAY

On the campaign trail, Donald Trump vowed to "quickly and decisively bomb the hell out of ISIS," and he appears to be following through on that promise. On Thursday, the White House said U.S. forces dropped one of their largest conventional weapons, known as the Mother of all Bombs, on an Islamic State tunnel complex inside Afghanistan.

Stepped-up air pressure is a valuable part of the campaign against ISIS targets in Iraq, Syria and Afghanistan. But the attacks come with a major risk of civilian casualties. Even accidental bombing of civilians — the military's euphemism is "collateral damage" — is a human tragedy that spawns new enemies, fuels insurgencies and diminishes America's moral high ground for condemning atrocities by the likes of Syrian President Bashar Assad.

Already, there are indications of a growing number of civilian deaths resulting from anti-ISIS bombing campaigns. According to some estimates, up to 200 people died during a March 17 airstrike in Mosul, Iraq's second largest city. It was potentially the largest single loss of innocent lives to U.S.-led coalition strikes since the fight against the Islamic State began in 2014. The U.S. is investigating.

Airwars.org, a non-profit organization, says alleged civilian deaths from coalition airstrikes in Iraq and Syria rose from 585 in the last quarter of 2016 to 2,580 in the first quarter of 2017. The group acknowledges, however, that many of the reports are unconfirmed.

Nation’s warriors protect innocents: Opposing view

The Defense Department says the White House has not relaxed rules of engagement in Iraq since Trump took office, although there are conflicting reports from senior Iraqi officials. The Pentagon is adamant that it takes such risks seriously. "There is no military in the world that has proven more sensitive to civilian casualties," Defense Secretary James Mattis told reporters late last month.

One problem, however, is that the U.S. plays only a supporting role in Iraq. The combat air controller who has eyes on the target building is most often an Iraqi, not an American. The ground commander who chooses to call in an airstrike — rather than take the dangerous, if safer-for-civilians, step of clearing the building room by room — is typically an Iraqi officer.

The U.S.-led air coalition ultimately decides whether to grant the request for a strike, but under these kinds of arrangements tragedies can and have occurred. When Afghan forces called in an airstrike against Taliban fighters during fighting in the northern city of Kunduz on Oct. 3, 2015, human error, mechanical failure, fatigue and a high operational tempo led a U.S. Air Force gunship to fire for 30 minutes on a Doctors Without Borders hospital, killing 42 people.

Just this week in Syria, bad targeting coordinates led to a misdirected coalition airstrike that killed 18 Syrian fighters allied with the United States.

Mosul, where an estimated 400,000 people are still trapped in western sectors under Islamic State control, is a particularly hellish fighting environment. It's an area of dense housing and narrow streets where the depredations of the militants against civilians — including executions and the use of children as human shields — play out in real time on the video cameras of coalition surveillance aircraft.

Beyond Mosul is the U.S.-supported effort by Kurdish and Syrian rebels to capture Raqqa, a city of 220,000 in Syria that serves as the Islamic State's de facto capital. A U.S. Marine Corps heavy artillery unit has been brought in to hit targets when there's poor weather for airstrikes.

Trump vowed in his inaugural to wipe ISIS "from the face of the earth." While it's impossible to avoid killing civilians in that mission, particularly those placed in harm's way by terrorists, it's worth remembering that every innocent who dies at the hands of U.S. forces leaves survivors who might come to hate America and seek revenge.

USA TODAY's editorial opinions are decided by its Editorial Board, separate from the news staff. Most editorials are coupled with an opposing view — a unique USA TODAY feature.

To read more editorials, go to the Opinion front page or sign up for the daily Opinion email newsletter. To respond to this editorial, submit a comment to letters@usatoday.com.