Why did cops in NYC search my bag on the subway for no reason. Meanwhile Mex/Canadian borders are wide open?

Since 9/11 people are scared that we will get attacked again. I think what happened to you is stupid. But having these extra precautions the Government thinks that the people will think we are safer now. If a terrorist really tried hard enough no amount of security will stop them. Since 9/11 occurred it is harder for terrorist but I think eventually we will be attacked again. Bush has made a lot of enemies in the world nearly every country in the world hate us now. As for the mexican borders they are building a fence to "keep" people out but they will find other ways to get in too. I don't believe no amount of security will stop someone if they really want to get in or attack us. AS far as Canada goes we are stil allies with them but eventually I think stronger measures will be taken place there too. If the government had thier way we would be a police nation with no freedoms. The plane security is totally crazy they are going way too far I think.