For those in the John McCain camp who spent the last week of the campaign declaring that Barack Obama hung around with antisemites, the appointment of Rahm Emanuel as chief of staff is a bit of a stunner. To anyone living in the real world, it comes as a revealing first move.

If you were expecting Kumbaya from Obama, do try to remember where he learnt politics. It’s Chicago, where Emanuel also practised the dark arts of twisting arms, yelling in people’s faces and counting votes. As one wag put it, Emanuel as Obama’s chief of staff is “Change you can f****** believe in”.

Rahm comes from a remarkable family. One brother, Ari, is the Hollywood agent for Sacha Baron Cohen, Mark Wahlberg and Larry David. If you’ve watched the television series Entourage, he’s the model for the character of Ari Gold, played by Jeremy Piven. His other brother, Zeke, is a Harvard bioethicist (and an old classmate of mine) who also manages to make the nuances of healthcare reform sound like a fax machine transmitting. None of them, it is fair to say, is known for pouring oil on troubled waters.

Rahm Emanuel himself explodes amusingly at regular intervals and uses language that might have made Richard Nixon blush. But as his friend Todd Purdum, the Vanity Fair journalist, has noted, he also lives by the Franklin D Roosevelt truism: “Keep all the balls in the air without losing your own.”

He gets things done. As the fourth highest ranking member of the Democratic leadership in the House, he has a very good idea of where the votes are, who the problem congressmen will be and how to corral, bully and pinion the wayward to get his way. As a junior member of Bill Clinton’s 1992 election team, he focused relentlessly on fundraising – and it paid off.

He remembers enemies well. The most celebrated anecdote about Emanuel was after the Clinton campaign, when he denounced the names of Democratic insiders who had sided with the other candidates.

As Elisabeth Bumiller of The New York Times reported more than a decade ago: “Emanuel grabbed his steak knife and, as those who were there remember it, shouted out the name of another enemy, lifted the knife, then brought it down with full force into the table. ‘Dead!’ he screamed. The group immediately joined in the cathartic release: ‘Nat Landow! Dead! Cliff Jackson! Dead! Bill Schaefer! Dead!’”

Quite how his appointment will go down in the Middle East is an interesting question. The Emanuel family hails from Israel. They were originally the Auerbachs, but after their uncle Emanuel was killed in a clash with Arabs in Jerusalem in 1933, the family adopted his first name as their last. Emanuel, in other words, has serious Jewish and Israeli cred. But that doesn’t mean he’s a Likudnik.

His friend Jeffrey Goldberg, a writer for The Atlantic magazine, captures the dynamic well: “Rahm, precisely because he’s a lover of Israel, will not have much patience with Israeli excuse-making, so when the next [Israeli] prime minister tells President Obama that as much as he’d love to, he can’t dismantle the Neve Manyak settlement outpost, or whichever outpost needs dismantling, because of a) domestic politics; b) security concerns; or c) the Bible, Rahm will call out such nonsense and it will be very hard for right-wing Israelis to come back and accuse him of being a self-hating Jew.”

In other words: he’s a sign of Obama’s seriousness about governing. He’s no suck-up like Andy Card, George Bush’s former chief of staff; and he’s no patsy. People will be scared of him – which can be helpful when you’re as congenial, if aloof, a man as Obama.

Rahm, remember, helped to shepherd two of Clinton’s more successful initiatives through Congress in his first term: the crime bill and Nafta – the North American Free Trade Agreement . He also managed the Democratic comeback in the 2006 elections. Ray LaHood, the Illinois Republican congressman, conceded at the time: “He legitimately can be called the golden boy of the Democratic party today. He recruited the right candidates, found the money and funded them and provided issues for them. Rahm did what no one else could do in seven cycles.”

He is a ferocious Democrat but, like his brother Ari, loves making deals. He comes from the moderate, centrist wing of the Democrats, the Democratic Leadership Council, and is extremely close to the Clintons. Back in early 2007, he faced a real quandary in picking between Hillary Clinton and Obama in the primary. When the Chicago Tribune asked him whom he was supporting, he responded: “I’m hiding under the desk.

I’m very far under the desk and I’m bringing my paper and my phone.”

That’s also part of the appeal for Obama. The Clintons remain powerful in the party and Hillary will be essential to getting healthcare reform. By picking Emanuel, Obama has opened up a key channel to his former rivals.

Some Republicans also find Emanuel easy to deal with, even with his abrasive manner. McCain’s closest Senate buddy Lindsey Graham was one of those offering praise last week: “I worked closely with him during the presidential debate negotiations, which were completed in record time. When we hit a rough spot, he always looked for a path forward. I consider Rahm to be a friend and colleague. He’s tough but fair. Honest, direct and candid.”

Still, there are worries. In 2000, Emanuel was on the board of Freddie Mac, the now disgraced mortgage public-private entity whose overly generous loans helped to bring about the financial meltdown of the past two months. He has received a huge amount of campaign money from hedge funds, private equity firms and the financial industry. He unnerves some liberals because he is a brutal pragmatist and deeply aware of the danger of overreach.

We can read too much in a single appointment, but the alternative to Emanuel is revealing. It was a mentor to Obama, the mild-mannered, scholarly, left-liberal Tom Daschle. It’s hard to think of the choice of Emanuel over Daschle as anything but a clear decision by Obama to govern effectively from the centre, with meticulous organisation and a pitbull edge if necessary.

It suggests to me that Obama knows that handling a Congress with a big majority but with many more Democrats from conservative states will be one of his most difficult and urgent tasks. Sometimes you need an enforcer. Revolutions do not make themselves.

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