Firewall isn't really centralized enough to have a real investment in anyone's status quo. It's even possible that if a revolution occurred in the solar system somewhere, Firewall would end up pursuing goals on both sides in the name of stability. My limited understanding is that Firewall isn't terribly concerned with what it's members do so long as it doesn't compromise Firewall, or their ability to help. That probably means Sentinels shouldn't go starting revolutions though. In the event of a major conflict between major solar system powers, Firewall has likely already failed. In that case I'm not sure what they can do when antimatter armed fleets let fly, and RKKVs become real military options. Firewall doesn't have a fleet or anything, so they're limited to covert actions to force an end to the fighting. What exactly that means depends a lot on the nature of the conflict.