We abolished biological and chemical weapons because they are considered obsolete tools of war after nuclear was invented. Who enforces the abolishment of bio/chem? States with nuclear arsenals. There’s little appetite in nuclear powered nations for nuclear disarmament. There is appetite for nuclear nonproliferation among nuclear powers, in large part because it maintains the power imbalance.

If you want to push for nuclear disarmament you’ll have to find a different model than bio/chem disarmament.

It's worth noting that the USSR actually kept a lot of anthrax warheads on ICBMs in a counter-value (i.e. against cities) role. But yeah, they're basically only useful for threatening revenge and aren't for actually fighting for the same reason that chemical weapons aren't.

https://acoup.blog/2020/03/20/collections-why-dont-we-use-ch...

>Why haven't we abolished nuclear weapons like we have with Biological and Chemical

If you believe that the US does not develop, test and have ready bio and chemical weapons then I got a bridge to sell you.

there is a political theory called Mutually Assured Destruction that has been the bread and butter of nuclear arms diplomacy since the 50s.

Because it's unenforceable, and nuclear weapons are the only deterrent against foreign invasion, which is a why many nations have desired to acquire them.