The number one responsibility of the federal government is to provide for the defense of our country, and now more than ever, that includes protecting our defense systems and civilian infrastructure from damaging cyber-attacks. Recent events have shown that the United States is not immune to a cyber-attack from hostile foreign actors. Even more alarming, our adversaries have determined that the reward outweighs the risk of launching a cyber-attack against our nation. It is the newest, most sophisticated form of attack threatening our national security today. A cyber-attack on our critical infrastructure, including electric grids, transportation systems and water supplies, could cause significant destruction, or worse, lead to loss of life. As chairman of the Senate Armed Services Subcommittee on Cybersecurity, I will work with my colleagues in Congress, the administration, our military personnel and other stakeholders to develop policies that will protect the United States from damaging cyber-attacks.