Enrichment

I have always maintained the Iran is not trying to make a nuke but they are using the possibility to gain leverage for other things. They already got billions of dollars and sanction relief and they will continue this strategy as long as it works. The US has the right to inspect their non-military sites as long as they get 24 days advanced notice. The US has no right to inspect their military sites. If Iran chose to start making a nuke they could easily hide their activity under the current rules. Anytime they choose they could quickly make enough enriched uranium to make a nuke.. The enrichment of uranium is a non-linear process meaning that it is easier to go from 20% to 90% than it is to go from .7% to 20%. A practical illustration of nonlinearity is that Iran — or any other nuclear hopeful — needs increasingly fewer centrifuges to make uranium 235 increasingly potent. For instance, one industry blueprint features 3,936 centrifuges for enriching up to 4 percent, 1,312 centrifuges to 20 percent, 546 centrifuges to 60 percent and just 128 centrifuges to 90 percent — the level needed for a bomb.