With the killing of Osama bin Laden, Barack Obama’s presidency has taken a new course — and so has America, and the world.

Obama is winding up the Bush era of large-scale territorial war, and substituting for it targeted, limited missions, favouring assassination (often by third-party forces), strategic bombing and air operations.

The strategy — which will presumably be given a boost by the cache of information obtained from the bin Laden raid — will allow the US to do further damage to the already frayed and scattered al-Qaeda organisation.

Though al-Qaeda has never been any sort of real threat to the US or other Western states, it was able to land a few lethal blows for a few years. That power was much diminished even before bin Laden was killed; now its activities are largely confined to the Arab world.

Arguably, its continued operations there strengthen the US by obstructing the genuine political development as expressed by the “Arab spring” uprisings.

Nevertheless, the outfit remains defined against the US, and by gradually winding it up, Obama will be dealing with a genuine enemy. Should the missions be conducted with minimum civilian casualties and civil disruption, it will make his country safer (a few botched ops, and the reverse will be the case).

Politically, the strategy may yield great or greater rewards at home. It’s a way for Obama to become a foreign policy President for the second part of his first term, but also to differentiate himself from the Bush era.

Obama will identify himself with targeted, well-planned operations, success, modest claims and real achievement. By contrast, the Bush era will increasingly be seen as the era of sprawling, badly executed disasters, failure, bombastic declarations and geopolitical fantasy.

Thus, the remnants of the Bush era will be subsumed into Obama’s agenda. Quite likely that will involve a simultaneous push against al-Qaeda outposts, a deal with the Taliban and an announcement of a substantial Afghanistan withdrawal.

The post-territorial nature of the anti-al-Qaeda offensive will be presented as a new form of liberal projection of power — modular, efficient, franchised, low cost in American lives. Essentially, it’s a type of postwar that can be sold to conservatives and much of Obama’s liberal base.

Conservatives will like the unilateral projection of power, and the assertion that the US remains a special case that can breach others’ sovereignty at will, in protection of its own.

Liberals will like the absence of swagger, the creation of a type of “smart” postwar that applies all the features of the world in which liberals live — networked solutions, abstract project management, minimal environmental impact — which will make it appear natural to many of them.

The involvement in Libya, rather then being the third in a series of neocon wars, is really the first in these series of postwars, incursions more limited even than Clinton’s Balkans campaigns.

The efficient management of such a strategy will leave conservatives nothing to say. They will not be able to accuse Obama of “cutting and running”, since targeted missions will be the context in which selective withdrawal is occurring; any appeal for more “boots on the ground” will simply remind the country of the pre-Obama era when nothing went right.

Liberals will not be disturbed by the multiple breaches of sovereignty, as long as it does not involve territorial occupation. When the antiwar left (and the libertarian right) object to such extension of power on sovereignty grounds, it will sound archaic, old-fashioned.

Non-territorial postwar cuts with the grain of a borderless world; it’s the Amazon/UPS/Netflix war — there as soon as you order it (and the occasional f-ck up).

Such a strategy — call it ultrawar, “ultra-” in its meaning of “beyond” — has further political ramifications. It conforms to the unique powers of the US President, a leader who can do whatever he likes abroad, but can’t change the parking laws in downtown Boise.

Obama’s steady, ordered, “ultrawar” will, should it go well, compare favourably to the continued tepidity of the American economic recovery. Obama will have to wear responsibility for that too, but it will be shared with the Republican-controlled Congress — and, if Obama can gather some residual political skills, he will be able to sheet most of the blame home to it.

This policy is already providing political dividends. Following the bin Laden raid, Obama’s presidential approval numbers are at 51%. Whether they will last remains to be seen (as every conservative columnist has noted) — but it’s worth comparing the approvals ratings for Congress.

Four months after the Democrats ceded control of the House of Reps, and the face of Congress became that of GOP leader John Boehner, approval ratings of Congress have hit … 20%, where they were under the Democrats.

Doubtless, Obama can lose this current lead, but the Republicans are beginning to realise that they’re boxed in a corner. They no longer have the cache of insurgency of 2009-2010, headed by the semi-real Tea Party movement.

The Tea Party has now been stood down by Fox News and FreedomWorks and the other lobby groups that funded and organised them (neither TeaPartypatriots nor TeaPartyexpress, the two major, feuding Tea Party groups list any events on their websites, which have become ghost net-billboards).

There are two major problems for the Republicans. The first is the debt ceiling, the official limit on how much the US can borrow, set by Congress. Since Congress also ratifies the money borrowed, the ceiling is a ridiculous entity, a tool of politics. The US will hit its current limit — $14.6 trillion — on May 16, but no agreement to raise will have been negotiated by then.

The US has until early August before it would fully default. From now until then, the Republicans will play a game of chicken trying to extract concessions. But no matter how many they gain, they will eventually have to raise the ceiling — at which point they own the debt.

Their other problem is a growing split on foreign policy, as the hitherto minor conservative antiwar position begins to assert itself. The Libya involvement was a disaster for the Republicans, with mainstream figures such as Mitt Romney tucking in behind Obama, opportunists such as Newt Gingrich advocating it, then opposing it when Obama committed to it. Other conservative boosters have gone all the way across.

With that confusion, the clarity of Ron Paul’s position — opposed to all US militarism — has had a magnetic effect, drawing in the now fully fledged cartoon figure Sarah Palin, and tempting others to a variety of positions that diminish national security, and try to return the debate to the domestic sphere. This means the Republicans are going into the campaign with half a dozen positions on American power, i.e. like Democrats.

The whole thing makes for a dramatically reversed politics. It is unlikely to restore Obama to the full glory of 2008, or anything like it. But with 365 electoral college votes, the Republicans would have to take six or seven states back, and hold Missouri. They will need to be united, and on point, and last week they got caught up in a war.