White House Security Advisor Howard Schmidt said that increased vigilance by both businesses and government in the run-up to the war had kept cyber attacks to the minimum.
With the exception of limited denial-of-service attacks, which were easily dealt with, there were no major cyber security incidents, said Schmidt, speaking at the RSA conference in San Francisco.
"One of the biggest issues we were concerned about was whether there would be adequate defences against hactivist activity. There was a clear recognition that we would be watching for this, and people were much more diligent than they have been in the past," he said.
Any headline event raises the risks of cyber attacks, said Schmidt, but organisations prepared themselves for the war, by ensuring that patches were updated, and increasing their vigilance.
There were web defacement attempts, but they were caught and stopped, and internet service providers were able to deal with denial-of-service attacks before they had an impact.
Schmidt denied that the threat of cyber-terrorism during the war had been exaggerated, saying it was largely good preparation that kept its impact to a minimum.