Preemptive strike without formal declaration of war signed by congress and without congressional or U.N. approval. Plus, Bush, Cheney, Rumsfeld, and several of their legal advisors were charged and found guilty of war crimes in foreign courts for endorsing torture and cruel, inhumane, and degrading treatment of P.O.W.s but the ICC (international criminal court) decided not to pursue the matter even though they had ample evidence cause Murica.
Getting UN approval is a "nice to have", but it doesn't guarantee anything. A war of aggression would probably be something that could be prosecuted in the ICC as a crime of aggression, but to prove it's a crime of aggression you need to prove that there was no "just cause for self-defense". The whole basis of the US justification for attacking Iraq was that Iraq was involved in terrorism against the USA. So, to prove that it wasn't a war of self-defense, you'd not only have to prove that Iraq had no connection with any kind of terrorism against the USA and had no intention of it in the future, but that the US leadership knew that that was the case and invaded under false pretenses.
At this point we know that Iraq didn't have WMD, but can you really prove that the US leadership wasn't so deluded that they thought that Iraq genuinely didn't have WMD? The whole aftermath of the invasion involved a lot of embarrassing searching for WMDs that the US was sure were there. The US was constantly announcing that they were closing in on the WMDs, but every site they searched turned out to be nothing. If they'd known there really weren't any, they probably would have just gone ahead and planted some evidence. Instead, they kept looking and looking and claiming they were sure it was there somewhere.
Besides, the US has a veto on the UN security council, so they couldn't recommend prosecution or anything because the US would just veto the resolution.
were charged and found guilty of war crimes in foreign courts
Which foreign courts? Which war crimes in particular?
ICC (international criminal court) decided not to pursue the matter even though they had ample evidence cause Murica.
"cause Murica" is your reading of it. They had the option to charge Bush, but they didn't. One reason for that might have been that they knew they'd never be able to get their hands on the US officials they could have charged, and that the US might react really badly to the charges. But, another reason might be that they knew they'd never be able to get a conviction, because the bar to convicting officials is very high at the ICC.
"Evil shit" isn't the same as "crimes". The Bush admin did plenty of evil shit, but it's very hard to prove they broke any specific laws. Instead, because they managed to scare the shit out of the US, congress and the senate kept giving them as much authorization to do whatever they wanted. As for international laws, those are very rarely used, especially against superpowers, and the bar to proving anything is very high.
The wikipedia page you posted essentially just says "Iraqi Freedom was justified because of all of these things that we say are occurring" when it was proven that there were no WMDs, no nuclearization, etc. They violated the terms of a ceasefire? So that required 13 years of war? It was about Saddam and Bush Sr. That and creating a US military base in the middle east so that there would be a base of operations outside of Saudi or Iranian influence.
So, you missed this bit? It's right at the top of the page:
is a joint resolution passed by the United States Congress in October 2002 as Public Law No. 107-243, authorizing the use of the United States Armed Forces against Saddam Hussein's Iraq government in what would be known as Operation Iraqi Freedom.
can you really prove that the US leadership wasn't so deluded that they thought that Iraq genuinely didn't have WMD?
I can't be fucked to look up something that hasn't been relevant for over ten years, but the answer to this question is definitely yes. Do some research and it shouldn't be hard to find.