BBC News By James Clayton image copyrightGetty Images In Geneva last month, US President Joe Biden tried to set some ground rules for his Russian counterpart, Vladimir Putin. He said cyber attacks on critical infrastructure were "off limits". "I looked at him and said how would you feel if ransomware took on the pipelines from your oil fields? He said it would matter," Mr Biden said, He went on to say that if Russia violated these "basic norms" the US would retaliate. The events of the last few days will test that claim. On Monday, Bloomberg reported that Synnex, a third-party provider used by the Republican National Committee (RNC), had been breached last week.