Chuck Todd intended his castigation of Barack Obama on Syria as a preplanned “Gotcha!”, IMO. Why did he still go with it after Obama had clearly made it unsuitable? I see two possibilities:

1. Todd had a script in his mind for the interview and was so focused on the script he didn’t really notice what Obama had said. That’s the charitable version.

2. Todd didn’t really care that Obama had already mentioned ‘Syria’. He was playing to the anti-Obama peanut gallery. This is the non-charitable version.