What powers did the federal government get under the constitution?

What are the powers that the federal government gained under the Constitution?

The constitution really gives the central government little power except to abide and uphold the ammendments in the constitution. The "powers" that the central government has are a direct result of the need to have order in a democracy. Unfortunately we have come to a point once again (previously in the Cold War) that we are forced to give up our rights in the name of keeping our rights.... Doesn't make much sense does it? But there were terrorists and planes hijacked and WMD's and internet beheadings! So we are sinking our culture and our democracy to the level of the government of the one that the terrorists are more familiar with to fight the terrorists. The end never justifies the means. If you are evil for just a day for the sake of good, does that make you a good guy? What about the people that felt your evil? Wouldn't that affect their decisions and their actions? The only thing in life that is as necessary besides human rights, is a firm grasp on the laws of physics. For every action there is an equal and opposite reaction. This does not stop with the guy with the bigger stick.