Cache

In the last few days I've heard several news commentators talk about a *cache* of weapons,
pronouncing 'cache' as 'cash-A'. This pronunciation is wrong, yes? Should they be saying
'cache for' rather than 'cache of'?

They are indeed mispronouncing it. A cache is a hiding place for or a store of something hidden (at least according to the Americn Heritage Dictionary) so 'cache of' and 'cache for' are both appropriate

The errors in pronunciation committed by Americans in general are depressing: "cutter" for Qtar, "eye-rack" for Iraq, "al kayder" for "Al Qaeda". I know it's not always possible to pronounce non-English names like a native but it seems to me they ought to be reasonable facsimile.

Unfortunately, we Americans are led by a man who mispronounces half the words his ventriloquist gives him. Why should people be expected to make an effort when they hear "nucular?"