1. Argue with idiots (sounds like a book title doesn't it?) and hope at least one will do a fact check before they send another barrage of misguided missles at you.
2. Just don't expect any civil response and understand you're not going to change anyones mind, that way, you're not disappointed.
Have we not seen through the years a number of very dumb people who have a whole bunch of letters after their name? Passing test and all that can get you those letters. The good news is you do NOT have to have those letters to gain knowledge. Sooo, just maybe, if we can pull it off, we can plant little seeds of doubt at the validity of the information in their textbooks to children. That method has been used by the teaching system against our ancestors actions for years and it seems to have worked. That's why we are arguing with more idiots. That method worked over in the USSR too. I know, it's a shot in the dark, but you have the lamp. Find a kid and start talking. I know my Grands roll their eyes when I start talking but they've also remembered enough to actually call their history teacher on a few points.
Those Blogs and OpEd pieces are set ups. That game is rigged.