Later devices have relied on some form of explosive compression of a subcritical lump which is assumed to be a necessary technology to build miniaturised weapons.
However take this all with a grain of salt because I'm not a physicist with any real expertise in building these things, and much of the information in public literature is probably misleading. Any idiot can face a crisis - it's day to day living that wears you out.
But what do I know, I didn't even read the book, just saw Pierce Brosnan playing the Russian agent in the movie. Oye, vatos, dees English sink todos mi ships, chinga sus madres, so escuche: el fleet es ahora refloated, OK? — The War Nerd
