War crimes trials were created to punish people like Obama who target and kill civilians in violation of the Geneva Convention. It’s merely a matter of time before Obama’s crimes catch up to him in an international tribunal.

See:
http://www.commieblaster.com/obamacrimes/index.html
http://www.impeachobamacampaign.com/congressional-report-lists-36-pages-of-obamas-crimes/

The second invasion of Iraq was supposedly a result of Saddam violating the “no fly” agreement by his missile batteries targeting US aircraft with radar.

So I can see a legal argument that the U.N. authorization would not be required if an ally requests aid pursuant to a treaty.

Another issue is whether UN has any authority at all concerning the US because the US Constitution gave the war power to Congress, not the UN.

An original case might be made of the war crimes of using nuclear weapons such as depleted Uranium ammunition causing birth defects and illness, and torture and murder of POWs, etc., but the claim regarding legality of the war is probably not a winning argument.