Is Our Nuclear Arsenal a Partisan Issue?

Sure, if America builds tactical nuclear weapons there is a risk that there could be a nuclear war at lower levels of weapon size. I've noted that anything targeted by a nuke of any size will fail to appreciate the distinction between "strategic" weapons and "tactical" weapons.

But there is also a risk of not having a robust "tactical" option. If an enemy with a "tactical" option thinks America would never risk an escalation to "strategic" weapons, that enemy might be more likely to use their "tactical" nukes feeling America has no choice between accepting enemy use of small nukes or escalating to large nukes that might simply lead to the enemy using "strategic" nukes on American cities.

So of course a "small" nuclear exchange isn't good. But despite its awfulness, it is better than a "strategic" exchange.

And isn't arguing that any nuclear weapons use automatically leads to all-out nuclear war, as Senator Feinstein does, rather an odd position to stake out?

Well, the post-Cold War/Soviet era holiday from MAD was nice while it lasted.