I am almost cynical enough to believe that a modern neoliberal president surrounded by hawkish advisors could be convinced quite easily to personally kill the keeper and retrieve the launch codes. I believe that the hawkish "at any cost" mindset of modern American politics distorts human empathy so much that it's completely within the realm of belief for me for this to occur.
More likely, I think, that those holding prestigious enough office can find ways to get around very high procedural barriers like this one by assigning the task to a secret service agent or other on-hand staff of a martial trade.
Personally I think we've seen plenty of evidence that those in high office might personally carry out and enable heinous acts of individual violence if the stakes are made to appear grave enough to them.
More likely, I think, that those holding prestigious enough office can find ways to get around very high procedural barriers like this one by assigning the task to a secret service agent or other on-hand staff of a martial trade.
Personally I think we've seen plenty of evidence that those in high office might personally carry out and enable heinous acts of individual violence if the stakes are made to appear grave enough to them.