There is a wise American saying: "If you are in a hole, stop digging." The six governments currently considering the next steps to prevent Iran from developing a nuclear bomb - the five permanent members of the UN security council and Germany - should heed that advice. Otherwise, they could end up without any handle on the Iranian nuclear programme and with only one (useless) option left: a military strike.
Yet the six governments seem determined to continue with what has been their strategy so far. Their condition for negotiating with Iran is a prior halt of its nuclear enrichment activities. Only in exchange for Iran's permanent renunciation of enrichment will they provide major rewards - from lifting all sanctions and trade restrictions to security guarantees.
This strategy has not worked and will not work. Under the nuclear non-proliferation treaty (NPT), of which Iran is still a member, countries are entitled to engage in enriching uranium for civilian purposes, and Iran claims that this is all it wants.
True, Iran's total halt of its enrichment programme would be welcome, not least because its government has hidden these activities for almost two decades from treaty inspectors, suggesting other than purely civilian motives.
But the issue of enrichment has been blown up into such a symbol of national sovereignty in Iran that no government there, never mind the Ahmadinejad administration, will climb down. Indeed, when the UN security council formally demanded a stop to the enrichment programme and imposed mild sanctions last December, Iran's defiant answer was to step it up.
So what to do now? The Bush administration, predictably, is pushing for new and tougher sanctions, based on an implied warning in the earlier UN resolution and arguing, as it did in the run-up to the invasion in Iraq, that the UN's credibility is at stake. But the only real test of UN credibility in this conflict is whether it can succeed in restricting Iran as much as possible to a purely civilian nuclear programme.
If the security council fails to agree on new sanctions - which is likely, given Chinese and Russian objections - it would be exposed as a paper tiger. If, on the other hand, it works out a consensus on more economic, and possibly even military, punishment, the UN's credibility would depend on whether these moves produced Iranian compliance.
That, however, is unlikely. Tougher economic sanctions will not force Iran to comply; instead, sanctions will merely hit this oil- and gas-rich country's trading partners. More threats will only push the international community further along the spiral of escalation and, possibly, into military action.
There are those in Bush's entourage who would like nothing better. While even a major air attack would fall short of destroying all of Iran's nuclear installations and, moreover, leave the technical knowhow intact, it might at least slow down the programme for a while and serve as a warning to other potential proliferators. But it is a foolhardy gamble.
Today, Iran declares that it wants to observe the NPT and that it has no intention of building a nuclear bomb. After a military attack by the US, both promises would be history.
If the six governments want to avoid the escalation spiral and curb the proliferation dynamic, they need to change strategy and objective. Instead of making a halt to uranium enrichment the be all and end all of their effort, their central objective should be to subject the Iranian activities to as much verification as possible: if Iran wants to enrich, so be it, but it must accept intrusive international inspections.
This is a bargain the Iranians themselves have repeatedly hinted at. The six have refused because verification cannot provide an absolute guarantee against the diversion of some enriched uranium to military use. But as the superpowers learned in the cold war, the absence of airtight verification does not render inspections useless. They would still submit the Iranian programme to greater restrictions than is the case today. And such an agreement would open the way to a wider agreement between Iran and the west for cooperation and regional stability.
That is why the six should stop digging a deeper hole. Instead of formulating new sanctions for the UN security council, they should use the next few months to explore confidentially what level of restrictions, combined with verification, Iran would consider in exchange for undisputed enrichment.
By all means, the six should keep the option of more biting resolutions as an inducement to Iranian compromise. But those who now call on the security council to issue rapid condemnations of Iran's behaviour should keep two things in mind: they are unlikely to have any effect, and the US has already used such resolutions as a pretext for launching military action on its own.
Christoph Bertram was formerly director of the German Institute for International and Security Affairs in Berlin.
Christoph Bertram’s work for Cif is copyright Project Syndicate, 2007.