US President Barack Obama assured outgoing President Shimon Peres, who was at the White House for a farewell visit this week, that the United States will not allow Iran to develop a nuclear weapon, and will continue to remain steadfast on topics central to Israel’s security in the nuclear negotiations.This is a reassuring message as representatives of the P5+1 (the US, Russia, China, France and Britain plus Germany) get set to sit down with their Iranian counterparts in Vienna this coming Wednesday for the sixth round of talks on stopping the Islamic Republic’s nuclear weapons program.Besides Obama’s promises, however, there are very few reassuring signs that Iran is willing to comply with even the most basic demands made by the US and other members of the P5+1.The two sides have reached tentative understandings on reducing the amount of plutonium – a second route to fuel for a bomb besides enriched uranium – that will be produced by a heavy-water reactor under construction near the town of Arak. And there are reports of a possible compromise that would turn a deep underground facility called Fordow, where there are 3,000 centrifuges, into a “research facility.”But there is no agreement on almost every other relevant issue. While the US and other P5+1 members want to reduce the number of centrifuges Iranians currently have to enrich uranium, the Iranians want to actually increase the number of centrifuges by over 10,000 from the current number of 19,000. Even if the number of centrifuges remain unchanged, Iran would be able to make a “dash” for a bomb in a few months, as US Secretary of State John Kerry noted in comments made to the Senate in April.There are other unresolved disputes, including whether Iran would have to reveal to international inspectors work that it is suspected of doing on weapons design in the absence of conclusive proof.Senior American negotiator Wendy R. Sherman, undersecretary of state for policy, was diplomatic yet clearly pessimistic when she said she doubted whether “Iran is really ready and willing to take all the steps necessary to assure the world” it has no desire or ability to produce a nuclear weapon.Iranian duplicity regarding its nuclear arms program is nothing new. But perhaps never before have the potential dangers of an Islamic Republic with nuclear capabilities been so evident. The Islamic Republic’s aspirations to expand its influence throughout the region are not just hypothetical. Iran is capitalizing on the dissolution of old national borders. The Iranians are providing troops, weapons and advice to Bashar al-Assad’s regime in Syria and expanding their influence in Lebanon via their proxy, Hezbollah.In Iraq there are reports that Iranian drones are being used against Al Qaeda-affiliated, Islamic State in Iraq and Syria (ISIS) forces. And if it has not already begun to send troops into Iraq to carve out territory for a Shia state, Iran might begin to do so soon. There are reports that Shia forces fighting in Syria against Sunni opposition groups are now heading to Iraq. Hezbollah, meanwhile, may be sending more militants to Syria to replace them.The US and Israel actually have an interest in seeing Iranian- backed militants battle it out against ISIS forces and weaken one another. In fact, as the Islamic Republic increasingly becomes over-extended in Syria and Iraq, and as sanctions continue to take a toll on the Iranian economy, Iran might be more willing to make concessions on its nuclear program.At the same time, however, the Iranians are even more desperate than ever to attain nuclear weapons capability.They realize that having a nuclear bomb would be a game changer in the Sunni-Shia clash. They already have the missile capability to hit almost every capital in the Middle East, but the Iranians would not have to actually use their nuclear weapons. The very fact that they have them would provide the Islamic Republic and their proxies in Syria, Lebanon, Iraq and the Gaza Strip ‘a nuclear umbrella.’ Any group or state attacked by Iran or one of its proxies would think twice before striking back against so powerful an enemy.That’s why it is imperative for the P5+1, who convene in Vienna next week for the sixth round of negotiations with the Islamic Republic, to keep in mind precisely what is at stake.