It’s been an open secret for a couple of weeks now, but this morning Barack Obama made it official by nominating former Republican senator Chuck Hagel to be his new defence secretary.

Congress was already shaping up for a busy couple of months, with ongoing budget issues and planned moves on gun control. Now the Senate will also have to deal with a confirmation debate. For, despite the fact that he is a former colleague, Hagel is not popular with the Republicans (he endorsed Obama in last year’s election) and his approval is not guaranteed.

Most of the publicity about Hagel so far has focused on his allegedly anti-Israel views, but the issues involved are much broader than that. In fact, the tone of the controversy merely serves to confirm Hagel’s point that the obsession with Israel tends to distort the whole national security debate in America.

What makes Hagel such an interesting nominee is that he seems a sceptic of a lot of the received wisdom on defence issues. With politicians on both sides generally afraid to touch military spending or to criticise the Pentagon, Hagel has been a (sometimes lonely) voice of reason, criticising the rush to military solutions. As historian Juan Cole says in a typically thoughtful endorsement: “Hagel is cautious about wars and what they can achieve, and has become more cautious over time”.

Although Hagel voted for the Iraq war, he later regretted that position and became an early advocate of withdrawal. He is also at least as keen as the president, and possibly more so, to get American troops out of Afghanistan, where he seems to realise they are doing more harm than good. But as a veteran of the Vietnam war and winner of two Purple Hearts, it will be difficult to paint Hagel as a coward.

American politics is so much in thrall to the defence establishment that it would be good to have a moderate in the secretary’s job. But it’s particularly important at a time when the deficit problem has reached such prominence. The Republicans claim they are keen to cut spending, but so far have shied away from the area where that is most obviously possible, namely the defence budget.

Obama’s leverage in the negotiations over the next couple of months will depend to a large extent on his ability to drive a wedge between low-spending and pro-military Republicans. The design of the automatic spending cuts, which include the military and will come into effect if no agreement is reached before March 1, give him the opportunity, in John Chait’s words, “to pit elements of the Republican coalition against each other”.

In that context it would be very valuable to have a credible defence secretary arguing that the Pentagon does not in fact need all the money that Congress keeps throwing at it, and that the wars the Republicans are keen to engage the country in — most obviously against Iran — would be foolish and unnecessary.

And this of course is where the question of Israel comes back in. Israeli prime minister Benjamin Netanyahu, who faces an election in two weeks’ time, sided openly last year with Obama’s opponent Mitt Romney and can now expect no favours from the Obama administration. But although that seems to have led him to turn the temperature down a little on the Iran scaremongering, it has not halted his Likud party’s slide towards the far right, or its determination to bend American politics to its own advantage.

As he now appears to recognise, Hagel should never have used the term “Jewish lobby” to refer to what would be better described as the “Likud lobby”: the powerful voices in Washington who maintain that no Israeli government, however extremist, can ever be blamed for anything. Hagel is surely right to argue that Israel’s interests as well as America’s are better served by reining in the militaristic rhetoric and opening the path negotiations, with the Palestinians as well as Iran.

We can look forward to having these issues canvassed (and no doubt distorted) in the coming Senate debate on Hagel’s nomination. With a 55-45 Democrat majority in the new Senate, and with Obama very clearly putting his authority on the line, it’s hard to see the opposition to Hagel being successful. For good or ill, the president will get his man in the Pentagon.