District 2 Avalanche

I just read the part when the rebels destroy the mountain in District 2 with avalanches and I can't help but to agree with Katniss on the issue. If I were Katniss or anyone of the rebels I would have no problem killing President Snow or anyone directly associated with the Capitol because I'd know that they would not hesitate to do the same to me. However, this attack seems to be more malicious because it is killing hundreds of people who as the book stated may not even be full supporters of the Capitol, it is even pointed out that some of the people in the mountain are actually District 13 spies. The fact that they killed these people without first giving them a chance at changing their minds and joining the rebellion rubs me the wrong way. I feel as though their disregard for human life is almost as bad as the Capitol's sometimes. What do you think?