McCain would exclude Russia from G8 nations

"The war in Iraq cannot be wished away, and it is a miscalculation of historic magnitude to believe that the consequence of failure will be limited to one administration or one party," he wrote.

McCain said if elected he would set up a new intelligence agency patterned after the Office of Strategic Services, the World War Two predecessor to the CIA, to fight "terrorist subversion around the world and in cyberspace."

"It could take risks that our bureaucracies today rarely consider taking -- such as deploying infiltrating agents without diplomatic cover in terrorist states and organizations -- and play a key role in frontline efforts to rebuild failed states," he said.

To fight climate change, McCain said he would do what the current administration has refused to do. He would agree to set reasonable caps on emissions of carbon dioxide and provide industries with tradable emissions credits.