Njúka, kleyfsa or sveppa (to nuke)

1) kleyfsa:
If there wasn't any possible way to make a short verb equivalent to English verb 'nuke', I would use 'að kleyfsa', the verbal form of the name Kleyfsi, the name of an 18th century Latin grammar-school handbook.
Kleyfsi k. (18. öld) nafn á latn. -ísl. orðabók frá 1738. Nucleus latinitatis. Líklega einskonar gæluorðsmyndun skólapilta af fyrri lið latneska titilsins, nucleus (from which the verb 'to nuke' is derived) = kjarni. (Íslensk orðsifjabók)
The funny thing about this, is that the phonetical ravages of the Latin word nucleus by 18th century grammar-schoolboys resulted into a word (kleyfsi), of which the unsuffixed part sounds identically with the stem of the adjective 'kleyfur', which links the word 'nucleus' with the concept of 'nuclear fission'. In the 18th century, no one had any clue about the structure of the atom let alone about the fact that isotopes of heavy elements could be split resulting into an incredible burst of energy. As for atomic theory, science hadn't evolved any single bit further than what the Greek philosopher Democritos hypothesized more than two thousand years earlier: an unfissile, uncleavable unit of matter, which he called 'atomos' (undividable, unfissile). Without them or anybody else ever being aware of this, 18th century Icelandic grammar-schoolboys gave a hint to a key phenomenon in nuclear physics, a 20th centruy science. What a weird coincidence!
Yes, kleyfsi and its verbal derivation kleyfsa are latisisms, but they are so dramatically cannibalized, thanks to phonoadaptative endeavours of 18th century Icelandic schoolboys that it can almost be regarded as being "genuine". So if there was a need for an equivalent of the English 'to nuke' (until now the long and troublesome 'gera kjarnorkuárás á' is used) I would prefer kleyfsi above the Anglophile construction 'að njúka'.

2) njúka (nýk, njúkum, nauk, nukum, ég er nokinn)
If it is going to be 'að njúka' I would decline it like strong verbs on -úka, because they all (except for 'strjúka') display some semantical relevance with regard to the idea of a "nuclear attack":
ljúka, lúka: the idea of 'ending something'
fjúka: also means 'to snow', scatter by the wind (could refer to the fall-out aftermath)
rjúka: smoke steam, blow away, all relevant in connection to the idea of nuclear attack.

3) sveppa
And last but not least, we have 'að sveppa' (to mushroom), refering to the form of a nuclear explosion, but this applies also to explosions in general, if they are powerful enough.)