It's an aberration. McCain can almost always be relied on to say or do the wrong thing. It's not suprising that Russert was surprised by this response, because McCain almost always is happy to be a tool of the leftist media in exchange for constant favorable publicity.
Yes. But Russert did cajole McCain into admitting thet "mistakes were made" in conducting the Iraqi war operations. McCain just provided a valuable sound bite with which the Democrats will bludgeon GW and the Republicans in the 2006 election season. The second tier argument below "Bush lied, there were no WMD" is "Bush won't admit mistakes, the war was not prosecuted well". McVain can always be counted on to carry the ammunition for the Democrats.