Hi all, guy who never posts but visits these boards regularly (mostly just for news). To clarify, in the Japanese dialogue, Shin refers to the RHE shells as "hannou dan," which translates to thermonuclear shell in English. For those of you who aren't familiar with the language, in the first ep, when the engineer tells Focker that the thermonuclear engines aren't ready, he refers to them as "hannou engine." Hannou means thermonuclear (although it can mean other things if you use different kanji). At any rate, the dialogue didn't mention anything about reaction weaponry, but I haven't done my homework enough to know what reaction weaponry is.
edit: gah! sorry, looks like I made a mistake. Please disregard what I wrote above. Anyway, the word for reaction in Japanese is pronounced "hannou." Shin uses this word to refer to the shells fired by the monster. In ep1, the mechanic also uses this word when talking about thermonuclear engines. This leads me to believe that "hannou" is also the Japanese word for thermonuclear, or a kind of military slang refering to something that is thermonuclear (instead of saying thermonuclear reaction engines, they say reaction engines, etc). I have no idea whether Macross is the only thing Japanese that uses this term this way or not, and I have no idea whether "reaction weaponry" is really an accurate translation, or if it is technologically different than regular nuclear weaponry. Any Japanese speakers who can shed some light?