"There's no such thing as a tactical nuke" is a common refrain among scholars, albeit skewed toward those not at military war colleges. The argument is that strategic use of a tactical nuclear weapon leads down the exact same escalation path as use of any other nuclear weapon. Moreover, that the very notion of a "tactical nuke" makes escalation more likely. You can disagree, and plenty do, but there's also plenty who don't disagree or at least don't want to find out.
> Moreover, that the very notion of a "tactical nuke" makes escalation more likely.
Sorry, but the notion exists, and the bombs exist. With n=2, likelyhood of nuclear escalation is hard to predict, but access to tactical nukes certainly hasn't increased the incidence of nuclear war so far.
I do think it's pretty hard to actually use a tactical nuke. If you use one against a nuclear power, it seems likely to escalate to mutually assured destruction. If you use one against a non-nuclear power, it seems likely to result in reprisal from the world, including potential nuclear response and therefore escalation to mutually assured destruction. I would think that the yield of the weapon barely matters, it's the fact that it's a nuclear weapon.
Who are these "scholars" exactly? The only reference I could find is Jim Mattis, and the context was very specific when he said that.
Furthermore, this is a "what if" scenario since tactical nukes have never been used. Of course it would make escalation likely during an open conflict, so what? Doesn't change the fact that there is a material difference between a tactical nuke and a strategic one.
Are you retconning Hiroshima and Nagasaki as usage of tactical nukes? And when they were not only used against an adversary without nukes, but at a time when the US was the only nuclear state, so that escalation was impossible?
The nominal definition of tactical nukes has less to do with yield and more to do with how they're used; tactical typically means a weapon designed for use on the battlefield.
If you have a real interest in this area, a subscription to Foreign Affairs would be useful. Especially during the 20th century that's where all these arguments were hashed out. Tactical nukes were already being publicly debated in the 1950s. You may be able to access many older articles, from Foreign Affairs and others, through a free JSTOR account.
In the cold war arms manufacturer got very creative: e.g jeep mounted nuclear weapons https://www.militarytrader.com/mv-101/the-atomic-jeep