The president as commander in chief signs off all military orders and as such "the buck stops here" in who to blame for the bad ones.
Secondly, you're completely ignoring the US backed Saudi attack on Yemen in which Obama sold $1.29 bil in smart bombs that, and I quote the human rights watch:
A few casualties is one thing, you and your administration killing thousands and wounding thousands more, a lot who were children, all civilians, is in my opinion at least worth looking into.
But we're the US so no one calls us on it for some reason
the US is a country built on the arms trade. was this $1.29 bil deal completed before or after the civilian bombings? if after, an investigation is definitely necessary. if before, you can only blame the us government for arming them, but the saidi coalition soldiers were the ones who pulled the trigger. ironically, the US also funded and armed the opposing forces of the civil war, which also committed several atrocities against civilians.
houthi fighters are a guerilla force and guerilla warfare prompts some of the worst humanitarian crises in history. its hard to accurately deliver ordinance to a target that routinely shoots and scoots behind the cover of a civilian population. armies have to make a tough call between endangering their soldiers or conducting less-than-ideal strikes on enemies hidden deep within towns and cities. it never excuses the mass killing of civilians, but stresses the need for more surgical weapons such as the US's prototype ninja hellfires which shred targets with minimal collateral damage.
all modern militaries should have a dedicated sector to preventing collateral and civilian casualties, but it's never properly funded or explored in wars where show of force and shock and awe are the invading forces' MO. for example, a mass civilian evacuation plan is impossible for armies that need a first-strike advantage to achieve their objective. letting the hostile force know exactly which cities and towns you plan on attacking is counterproductive and can potentially lead to more soldier casualties than a highly classified ambush operation.
war is hell, and the laws of war are routinely violated by all forces involved in combat. armies do the best they can to court martial war criminals after combat, but doing so during combat isn't possible when you need every soldier to be combat-effective and mobile. these decisions happen further down the pecking order than presidents or leaders are able to control.