HOUSE OVERSIGHT 018206 At the other end of the spectrum, using military means in the short term to guarantee prevention would entail a vast use of force -- essentially an unofficial, semipermanent occupation of Iran. This is not a viable path, particularly since other diplomatic possibilities have not yet been exhausted. Similarly, sanctions, while effective, are not sufficient by themselves. They must be intertwined with negotiations -- as Washington and its allies increase the pressure, cohesive and meaningful talks with equivalent concessions should follow suit. Some have argued that negotiations should expand to a "big for big" format, but decades of mistrust between the United States and Iran make smaller deals more practical. Such an approach would have to focus on ending Iran's most problematic enrichment activity: processing uranium to the 20 percent threshold, which makes the leap to weapons-grade material much easier. Instead, the regime could limit itself to 5 percent enrichment, and under strict supervision by the International Atomic Energy Agency. The intelligence community widely believes that although Iran has not yet decided to make a nuclear weapon, it is still moving to acquire all the necessary capabilities in case it chooses that path. Accordingly, Washington will need to obtain a concrete Iranian commitment to convert its stocks of readily upgradeable gaseous uranium into metallic fuel elements, which pose significantly less of a threat. A serious inspection system would need to be implemented in order to monitor these requirements. In return, the Iranians would expect the lifting of nuclear- related sanctions. They would also likely ask for acknowledgement that they have the right to continue their civil enrichment program, whether for supposed use in cancer treatment or to safeguard against a potential Russian decision to cease fueling the Bushehr reactor. Thus far, President Obama has been frustrated at the lack o