But, after the bombardment, very few were left alive on Earth. The survivors were over 90% residents of the SDF-1. All of them were UN-supportive. (All but one... Friggin Kaifun... I woulda had him thrown out an airlock, if I was Gloval...) Maybe later on, people warred once more, but I doubt it was UN/Anti-UN. It was probably UN/Terrorist Group. Or, as we have proof of, due to the purpose of Supernova, civil unrest in colony planets...
I will say this: The Zentraedi took 40 years to stop fighting. We ARE 99% the same, you know...