You are dreaming.
A carrier at sea is the ultimate military target. No civilians for thousands of miles.
No President could or would kill civilians over a purely military strike.
Clearly you don’t understand US military doctrine in these sorts of situations. If someone sank a fleet carrier that would be seen as an act of war and would lead to a nuclear level escalation within minutes.
As for targeting civilians, no one targets civilians directly in nuclear exchanges. They perform strikes on military targets—the fact that civilians are in the way is purely collateral damage.
Fun fact though: a strike designed to destroy military targets (which are hardened and require large ground bursts) are often more deadly to the civilian population than just outright targeting cities (which are air bursts and don’t create nearly the amount of fallout).