The other day a friend and I were discussing foreign cyberattacks and probes that appeared to be, if not government-launched, at least made with government protection and immunity. Prominent among these being Russian and Chinese hacking.
My friend suggested an imaginative use of letters of marque and reprisal, as authorized by the Constitution. These were the basis of privateering, perhaps the ultimate in privatization. The government would authorize the captain of a civilian vessel to seize enemy shipping, and sell it for his own profit. The letters ensured that if he was captured, he would be treated as a POW rather than as a pirate. A factor in ending the War of 1812 was that, while the US Navy was far too small to have an impact, American privateers (far outnumbering the Royal Navy) were inflicting great pain upon British merchant shipping.
The idea could be implemented along these lines: the US announces that unless a given country stops the cyber-raiding, the US will proclaim that the country is fair game for all American hackers and crackers. Do whatever you want, with no worries about prosecution. If you get any economic benefit, it’s yours. If you find any secrets, sell them (we get dibs on military and statecraft secrets, but you sell them to anyone else, too).