The UN security council’s deadline expired overnight, apparently without any Iranian move to suspend its uranium enrichment program. The United States says it will now press for tougher sanctions against Iran.

The US asserts that Iran’s nuclear program is designed to build weapons, although so far it has been unable to uncover any evidence for this.

Iran insists that the program is solely for peaceful purposes and professes itself willing to negotiate on the resumption of UN inspections, but it refuses to suspend enrichment as a precondition for talks.

Prior to expiry of the deadline, the US has been increasing its military presence in the Persian Gulf, apparently as a warning to Iran.

Earlier this week, the BBC reported on extensive American “contingency plans” for air strikes against Iran.

The contrast with the recent agreement with North Korea – which really had developed nuclear weapons, and proved it by testing one – is quite striking. The conclusion Iran is likely to draw, however, is probably the opposite of what the Americans are hoping.

If Iran’s leaders really are undecided about building a nuclear weapons capacity – if, as seems plausible, they want to build power plants but also want to keep other options open – then it’s easy to see how their reasoning might go: “North Korea had nukes; we don’t. The North Koreans got bribed, we get threatened.”

So the military threat could be sending quite the wrong message: that, in order to deter American attack, Iran needs to move to weapons production.

Upping the military ante also makes it less likely that the American troop surge in Iraq will be viewed benignly: that is, less likely that Iran will see it as bolstering the (basically pro-Iranian) Iraqi government rather than directed against Iran and its Iraqi allies. That in turn could make Iraq an even bloodier place.

Neoconservatives, like former UN ambassador John Bolton, who attacked the North Korea agreement as “appeasement”, were being dangerously unrealistic, but they were at least consistent.

Inconsistency in the Middle East could get us into still more trouble.