Why dis Bush's policies?

Why are people saying that Bush doesn't know what the he*l he's doing when he has served our country? It seems tp me that those who are saying that have never served their country and deserve to be put in on the front lines and see what it feels like. Yes i am piss*d but I think that we should busupporting him and not dissing what he has done. Think about it almost every war we the USA has been in a Republican was the one that got us through it. So why do people find it funny to dis him and disrespect him when they have never served or are to friggin lazy to serve.