A European diplomat would be satisfied with Iran having Japan's capabilities

I'm actually surprised to see this in the New York Times:

While the United States and Israel have not taken military options off the table, pursuing them is unpalatable, at least for now. Several American and European officials say privately that the most attainable outcome for the West could be for Iran to maintain the knowledge and technology necessary to build a nuclear weapon while stopping short of doing so. That would allow it to assert its sovereignty and save face after years of diplomatic tensions.

While that might seem to be a big concession on the part of the United States, Iran would first have to make even bigger ones: demonstrate that it could be trusted and drop its veil of secrecy so that inspectors could verify that its nuclear work was peaceful, steps Iran has resisted.

In other words, Iran would have to become a country like Japan, which has the capability to become an atomic power virtually overnight, if need be, but has rejected taking the final steps to possessing nuclear weapons. “If you’re asking whether we would be satisfied with Iran becoming Japan, then the answer is a qualified yes,” a senior European diplomat said. “But it would have to be verifiable, and we are a long ways away from trusting the regime.”

I'm sure the diplomat has qualifications in mind that were not stated. Most likely the qualification is that Iran can, according to him, gain legal nuclear weapons capabilities after proving to the US' satisfaction that its program is peaceful. What that would mean is just that the US would never be satisfied, so in effect, it would be the same permanent suspension of Iran's nuclear program that the West has been trying to achieve since 2005.

If "demonstrate that it can be trusted" means to accept an indefinite suspension to be lifted when the US gives permission, then Iran is never going to "demonstrate that it can be trusted."

I have to say, the West has all of these euphemisms, misleading and distortive statements about its position regarding Iran's nuclear program that it does become tedious. "Fulfill its obligations" means suspend enrichment. "Enter serious negotiations" means suspend enrichment before negotiations can begin as described in the UNSC resolutions.

However, if the West has a semi-reasonable set of verification measures, such as the Additional Protocols and increased monitoring regimens, then it can present its set and this dispute is over, because verification that Iran was not building an actual weapon has never been the issue of dispute in this conflict.