Originally Posted by
Primetime Harder
A cursory scan of the Resident Evil wiki indicates that they do indeed have a paramilitary wing.
"They used a variety of vehicles, including HUMVEEs. Complementing this security force was an air wing, which maintained a fleet of AV-8B Harrier jump jets, UH-60 Blackhawks, C-130 Hercules water-landing capable cargo planes, CH-53 Sea Stallion cargo helicopters for transporting prisoners and Hughes MH-6 'Little Bird' attack helicopters."
However, this equipment is far outclassed by pretty much everything Cobra has at its disposal. I'm also pretty sure that while Umbrella was busy getting crushed militarily, Destro would organize a hostile corporate takeover.