Ukraine is different and did the reverse, giving up their nukes. They said it was too expensive to keep them, which is only partially true. Ukraine could have deconstructed them and created new Permissive Action Links (PALs) in Dnipro although this process would have taken years and carried a high risk of accidental detonation or radioactive mishaps during the reengineering phase.
Honestly, I thought part of MAD was how, once a nuclear missile was launched, it would be better for other nuclear states to decimate the country of origin than to wait and figure out where it would hit.
Barring an attack on the US itself, the US under the current regime will never attack Russia. Whatever the kompromat happens to be, the President is completely bound by it.
The "kompromat" is the world's largest nuclear arsenal, some five thousand and change warheads, along with a delivery system that includes an HGV MIRV payload that can deliver a multi-megaton warhead at ~mach 20-something.