They're not laws, they're the exemption of laws, just like outlaws - "a person declared as outside the protection of the law". Terrorist means you're not protected by the law, do not get rights, don't fall under the Geneva Convention as a prisoner of war, etc. It means you get to go to Guantanamo Bay and rot for two decades without charge or anything.

But it's fine because it's the most powerful country in the world that does it. If anyone objects, they get dropped. If it comes to a vote in e.g. the UN security councel, they use their veto power.