In reports sent from Baghdad on 28 May 2007, in which Paul Wood commented on the talks between US and Iranian representatives, he clearly pronounced the word nuclear as [’nju:kyul@] (-@ representing the neutral vowel, schwa). This is very close to the pronunciation Pres. George W Bush uses, and for which he has been pilloried in the Press. It seems a strange mispronunciation to make, as the word clear is so common. What I think is happening is that the speaker - whether Paul Wood or ‘Dubya’ - is likening the word to those words which do end in -cular: e.g. jocular, vernacular, funicular, and also creating an assimilation of the vowel in the first syllable [ju:] to a second, non-orthographic, syllable, aided by the [l] which is darkened also by assimilation to the previous vowel.
Philip Belcher points out that the “correct” Latin pronunciation of ‘difficile’ is [di’fikilei]. He is right - for Classical Latin. The letter C was always pronounced [k]. However, the way in which English developed through the centuries meant that gradually the pronunciation of Latin words that were frequently used in English changed at the same time, and in the same way, so that C before AE, E, I, OE or Y came to be pronounced [s] - Caesar, Cicero, coeliac, Cymbeline. I don’t imagine for a second that Philip is suggesting we should go back to the Classical Latin pronunciations of these words. I’m sure that at no point did the English think they were moving away from the Latin pronunciation - just as they did not realise that their pronunciation of English words was changing at the same time.
Scientific terms - particularly the specific names of plants and animals - have generally been pronounced according to the traditional English development of Latin pronunciation - V as [v] rather than [w], AE as [i:], not [ai], and C as [s] or [k] depending on the following vowel (even ’sh’ in some cases - prima facie comes to mind). Therefore, the Latin word DIFFICILE becomes [di’fisili], just as facsimile is pronounced [fæk’simili].