Basically it’s a non-nuclear nuke, about 1/1000 of the Hiroshima bomb, which is to say still effing huge. The biggest conventional bomb ever developed, created during the Gulf War but never used (specifically because of the high risk of civilian casualities). Bigger than the Daisycutter by a lot.

It’s taking advantage of that fact that people in general are more accepting of weapons that simply cannot be used in a way that safeguards civilians, if they’re not nuclear/biological/chemical. People generally agree Hiroshima was bad, but nobody even knows what happened in Dresden, that sort of thing. It’s like getting people to notice cluster bombs and landmines really hurt civilians more than combatants and getting more than a shrug.

But it’s a very big boom. Like all WMDs, it compensates for other policy inadequacies. It terrifies the locals. And it sends a message: we don’t give a damn about any of you people, and we don’t care to find out if you’re against us or not. We’ll kill you first and call you a terrorist later. And the dead are harder to find/identify afterward than after, say, a sarin attack, so it’s better PR, as WMD attacks go.