Six months ago on 13 March, Bob Carr was sworn in as senator and foreign minister in one of the quickest personal transformations Canberra has seen for many a day. 

In less than a fortnight, Citizen Carr went from carefree commentator to cabinet. The man Mark Latham dubbed Bob the Blogger was happily chatting away on the web, following his Thoughtlines, seven years gone from politics, when a convulsion surged through Canberra and the dream job opened up. Step forward Senator Bob, sayeth the Prime Minister, and in the work of a magic moment it was done.

The elevation of the former NSW premier (1995 to 2005) echoed one of the recurrent habits of Australian politics: the use of Foreign Affairs as a fit place for former leaders. This was the method used with Hayden, Downer and Rudd. The theory is that it is an important job with the added advantage that it gets ex-leaders off the domestic stage and gives the former king plenty of time to bleed quietly while they travel the world in first class. 

Unfortunately for foreign ministers, there is not much movement in the other direction; Oz foreign ministers don't get a chance to step over the treasurer to the top job. Billy McMahon went from foreign to prime minister, while Evatt in the 1950s and Peacock in the 1980s made the shift to opposition leader, but couldn't manage the ultimate step. Whitlam was his own foreign minister for a couple of days when he was elected (and immediately recognised the People's Republic of China) while Menzies served as his own foreign minister for a period during his long rule. 

Being out of the country a lot doesn't offer too much time to build the numbers in the party room. Foreign ministers get to do the grunt work and prime ministers drop in anytime there's a chance to be presidential.

So far, the arrangement has worked just fine for Senator Bob. Carr does not fit in the Downer or Rudd category. In his case, being a former state leader was a big plus. Having beheaded The Kevin a second time in the caucus vote on 27 February (71 votes to 31), Gillard was buying a non-Rudd who came trailing his own gravitas.

The Carr shift happened at the Canberra version of light speed, and in that flash there was one illuminating moment that shows the huge gap between the words and thoughts of the private citizen versus what is needed of the public man. There's an ancient saying about the difference between being in or out of government which contrasts the man who has read the daily cables with the chap who hasn't read the cables. As Carr stepped up to his perfect job, he exposed for a moment the difference between one who is working on his instincts and he who has been constantly briefed. 

Before tracking Carr's performance over the last six months, the next column will consider his opening moments in the job, when the new foreign minister put his foot in it big time; a significant moment in the education of Senator Bob.

Photo by Flickr user AusAID Photolibrary.