I think we’re in an age when nuclear deterrent is actually less effective because the West is very unlikely to use anything like a nuclear bomb, whereas our adversaries might
Let's also consider the stances of those countries on a nuclear first strike:
China: Unambiguous "No First Use", with no exceptions
Iran: Doesn't even have nukes and afaik has been cleared of ever trying to do so by international inspectors
Russia: Reserves the right to use nuclear weapons if WMD are deployed against itself or its allies or if the very existence of the state is threatened with conventional warfare
The US: Still has full first use.
For fun, the other countries with nukes:
The UK: Has openly stated they will use nukes in a pre-emptive strike, officially has no stance on a "No First Use" policy in order to "keep its enemies guessing"
Israel: Doesn't have nukes (winkwinknudgenudge) but would 300% use them if they did
Not only that but the US spent the entirety of the Cold War trying to either use nukes again or find some way to deploy nukes to every soldier and conflict possible, with everything from nuclear demolition charges to artillery shells
Given their way the US would arm every soldier with a nuclear rifle if they could
You could apparently theoretically make an nuclear hand grenade using californium, but it's completely impractical since you would need 2,7 kg of it, while the yearly production is below 1 g and it have halflife of 2,6 year.
Carrying an ultra light nuclear device stripped from all possible parts to make it throwable also wouldn't help the health of user, but it's not like Uncle Sam ever cared.
Many years ago at reddit - I saw that somebody had made a nuke "Davy Crockett" joke. For about 10 seconds I had this dialog with myself in my head "That can't be real. But could it? But it can't. Davy Crockett? How can that be real. I'm the world's dumbest man - I'll google." I still can't believe they named it Davy Crockett.
the US deployed backpack-sized nuclear weapons to Europe for decades as part of a stay-behind Gladio type operation, whose intent was to detonate nukes guerilla style in a Soviet-overrun Europe
There was also a plan during the cold war in case of war where US would nuke every transport node in Poland (that is basically every city above 20000 inhabitants) to block Soviet and Polish armies from reinforcing East Germany. And of course it didn't plan to bomb even East Germany itself, they are not Slavs after all.