How else do you destroy an extensive underground tunnel and cave system being used by the enemy as a base of operations to carry out their regime of obscene terror? These are bad guys, dammit, who have invaded our peace and the peace of most of the Western world. Do you really not want them gone?
Trump's military top brass felt it was appropriate and they no doubt ran it by Trump, who said do what you gotta do.
I don't have a problem with using the MOAB to destroy said installations and the users of them. As I noted in my OP, I didn't even need to be told that they used the MOAB.
I have a problem with there being, subsequent to doing so, no credible and believable messages being issued that show why doing so was prioritized and highlighted over completing the defeat of ISIS in Syria and Iraq where it is far stronger than it is in Afghanistan and where we've for some two years or so been hearing, almost daily, that is where the ISIS problem is most pressing. I'm sure there are reasons, they may well be good reasons -- the preemptive one I posited early may be one and may be others -- but whatever they are, we who pay for all of what our military does, deserve an explanation for why, out of the blue, converting a mountain in Afghanistan into a pile of gravel is suddenly so important.
The news, since the event, has been babbling about "shows of strength" as a message to the DPRK and others. Well, you know what? Was there ever any credible basis for doubting the U.S.' military strength and capability? After all, the U.S. spends as much as on our military the next six or seven most powerful militaries on the planet. Unless someone can show me that all that "excess" spending goes to labor (or is entirely wasted, which, frankly, is even less plausible), administration, and maintenance rather than materiel and equipment, there's no reason to think the U.S. military is insufficiently powerful.
Is criticizing every decision made under the Trump administration more important to you than getting rid of ISIS/terrorism?
No.
we have to start actually fighting in order to win.
I agree with that. I don't know whether I concur that my government's decision to bomb a mountain in A-stan and than convert having done so into publicity "stunt" has, from a priorities standpoint, has much to do with actually winning against ISIS when all we've heard is that ISIS is strongest in Iraq and Syria. The fact of the matter is that bomb -- MOAB's official meaning is "Massive Ordnance Air Blast" -- is equally effective against targets that aren't bunkered in a mountain. I want to know why we didn't use it to utterly eradicate an ISIS position in one of the two places where, by all reports, we actually need to see ISIS "gone" sooner rather than later.