The thing with cyber attacks is they happen all the time and usually consistantly. They might prevent a million attacks but it takes just one penetration through to attack a system. I agree that hiring hackers may help, but only to a certain point. Really you need to know what the enemy is using and doing. This reminds me of all those spy movies of the 90s.
American authorities charge UK man with hacking Army, Missile Defense Agency and NASA websites:
A 28-year-old man from Stradishall, England has been charged in the United States with hacking into US government and military computers, stealing sensitive data and causing millions of dollars in damages. Ref. Source 5