I wonder at what point does SaaS become a national security risk in the event of a solar event, (biggest-ever) cyber attack, terrorist attack, or some other cal

I wonder at what point does SaaS become a national security risk in the event of a solar event, (biggest-ever) cyber attack, terrorist attack, or some other calamity that takes down the internet for an extended period? Having virtualization software like vmware as-a-service would cause 2nd-order effects if it couldn't phone-home to renew activation.