In another story it was reported that Tsarnaev’s name was in a list with over 500,000 other people, suggesting like emails to Hillary, there are just too many to keep track of. However, that story also provided some detail, only 5% of the 500k were US citizens or Resident Aliens (green card). That takes the number down to 25,000 total in the US - how many of those would be in the Boston area and thus prime suspects? The Boston metropolitan area has less than 1-1/2% of the US population, so Tsarnaev would have been one of less than 400 people of extreme interest - and they couldn’t make the connection? Or did politically correct procedures make any such quick analysis prohibited?
Then again - what difference at this point does it make?
Boston bomb suspect's name was on classified government watch lists