Well, that's more of a common nickname based on appearance than a definition, there's not really anything else smokelike about them except density. Calling someone a carrot-top doesn't make them a vegetable.
I would have thought similarly, but Wikipedia says otherwise (https://en.wikipedia.org/wiki/Aerogel). Perhaps a flame-front can't advance fast enough through a rigid structure?
Heat cannot spread through aerogels quickly, nor can the expanding hot air front spread further into the fuel, so I'm guessing only the outermost surface can be thermally catalyzed, and thanks to their incredibly low density there's not going to be a lot of other fuel within range of a burning molecule to absorb the energy before convection carries it away from the surface.
Has anyone actually managed to create a "vacuum-filled" aerogel? My understanding was that they were typically open-celled structures created by replacing the water in a gel with air. Though I suppose if the strength was sufficient you could encase it in an airtight skin and then pump out the air. That might have applications for rigid lighter-than-air craft, or as even more effective insulation. At least until a few days after a pinprick forms somewhere in the skin.
Of course the air can then be replaced by something else quite rapidly, giving them impressive absorption properties. Essentially they're an extremely low-mass sponge.
I'm going with movie-knowledge. A nuke blast is only large compared to conventional weapons. Anything more than a few miles away from the blast will be virtually unscathed, and even much closer to the blast you're mainly talking broken windows and a bit of radiation damage. And hitting a relatively small and valuable target like a city requires precision aiming.
The only really credible threat from a poorly aimed nuke is a high-altitude blast, which would knock out radio communications and spread the fallout over a large area. Messy and expensive, but not really something that lives up to the visceral "Eeek! Nukes!" response.
The problem is not North Korea - we could destroy what little threat they pose to anyone other than South Korea today in a matter of days, if that. And doing so would probably
The problem is that China would hardly sit quietly by while we decimate their ally, and *they* are a major threat. For China, the continued existence of North Korea is the best of a lot of bad options. While a land buffer has less military value than it used to, they still don't really want the US to have a stronghold right on their border. Plus they spent a lot of lives defending N.Korea from the US during The War, letting the US win now would dishonor that sacrifice. Neither do they want to lose cheap access to N.Korea's extensive mineral wealth Nor to absorb such a populous and dirt-poor region themselves.
So China is stuck in a similar can-kicking position - they keep propping up N.Korea while hoping that someone more tractable comes into power.
10.0 times 0.1 is hardly ever 1.0.