acronyms

Since when did acronyms become things that you can't pronounce? I always thought that the difference between an acronym and an initialization (or an initialism, as M-W calls it) was that acronyms are words like NASA and NATO, and not FBI, CIA, NSA, and IRS.
 
Why does this annoy me? And, why could I only think of government agencies?
 
And, just because word processors make allowances for kerning after a period, why is it so bad to put two spaces after one? I mean, I *like* the extra break. It tells me where I'm allowed to breathe a little more deeply, instead of just taking a short little gaspy thing at a comma. Is it because when I read, I hear it in my head? I hear the rhythm and the cadence, and I find that important? Or is it because I'm still mad that one horrible job at an ad agency beat the double-space out of me without my consent?
 
It's sooooo hard to know.
 
I'll talk another time about punctuation within quotes, and why American rules are stupid. But not now. I have work to do.