"24 60-ton Trident missiles". wow, so let's say each has a MIRV with 5 W88 warheads at 500KT each. That's about 120 independently targetable warheads (each 6-7x more powerful than the Fatman nuclear weapon dropped on Nagasaki) per submarine. Wikipedia says they are on 14 Ohio class subs operated by the US. That's 1,680 total but let's say only 75% are operational at a time. So the US Trident II SLBM cocked-locked-ready-to-rock capability is around 1.3K 500KT warheads alone. That's... a lot.
More like half active, a quarter in port or in light maintenance, a quarter in deep maintenance. Realistically, two always on station from each fleet, sometimes four. Enough to maintain second strike deterrence even with enemy attack subs to contend with.
It also important to note that once an SSBN launches, there will likely be return fire from either land or sea based ballistic missiles that will boil the ocean for 50nm, incoming in 30-60 minutes. So tactically it is hard to launch just one nuke... It's full commitment or nothing. Just another cheery aspect of escalation dynamics.
> So the US Trident II SLBM cocked-locked-ready-to-rock capability is around 1.3K 500KT warheads alone. That's... a lot.
Aside from overstating operational readiness, you also upped the W88 yield from it's actual 455KT and, while most sources do reported that 4-5 warheads per missile is typical, you assumed all in the fleet or W88s, while they seem to be a mix of W88 and 90KT W76.
So it's a lot less ready to go than you've estimated here.
