Spending a far larger amount on trying to find a cure or a vaccine (not that I think trillions is a valid number number)? I really don't think money should be your argument here. Also Russia and Iran have spent tons reinstalling the Assad regime. Overall the Arab Spring can definitely be considered largely successful (depending on your values) and pointing to the one failure in Syria is a little misleading. In either case, what's your argument? That Assad should've been left alone(I honestly wouldn't know, I believe Syrians believe him to be the lesser of two evils) or that the west, which has largely left the situation 5 years back, should help build them houses? Which probably also wouldn't contain the virus in time to save many lives, seemingly it can outrun itself in the time it takes to build those houses. We already possibly have a cure that's cheap to make.