To me, illiterate means not being able to read or write at all. Functionally illiterate means that they can read some, but can't handle instructions, contracts, or other things in day-to-day life. Yes, it's a common thing in the US, but not 50%. Most can read at a 5th grade level, at least. Our kids always do poorly in all subjects when compared to kids from other nations (damned socialists!). But this is nothing new. Been going on for decades. When I was in high school back in the early 1960's, the athletes were never failed because that would mean they couldn't play for the school, so teachers were pressured to pass them, no matter what. In small towns, the kids of the rich folk couldn't fail because their parents would mess with the teachers or school board. And so on. And so for many decades for many reasons, we've been graduating kids who should not have been passed. It's just easier for schools to pass the unqualified than to deal with irate parents (who never blames the kids) and lawsuits. Yes, our educational system is broken. But it was that way in the 1960's. Nothing new.