Yeah, but no President has ever launched a pre-emptive nuclear attack (saving WWII). And the likelihood of any President doing so has decreased over time. The only time the button would be pressed is if enemy missiles are in the air.

It may not have to be nuclear armed adversary. And it will cause a high probability of your own citizens dying. Not certainty.

It is exactly this line of thinking that makes it worthwhile creating extra barriers to make it harder to launch a strike to force the person responsible to be very sure.