No U.N. Resolution holds any law in a sovereign nation....

No U.N. Resolution holds any law in a sovereign nation.
International laws only hold sway as long as the participating country agrees to abide by those laws.
As with the Geneva convention and other war agreements a country can only be in contravention if they agreed to sign it and not all countries are signatories to such agreements.
Iraq wars were not sanctioned by the U.N.