JERUSALEM ( CNN ) -- Israel makes no secret that it sees Iran is its biggest threat but the scale of the threat is less clear cut . Israel 's recent military exercises are seen by some as a show of strength to Iran . Prime Minister Benjamin Netanyahu has not missed an opportunity to name Iran as the number one threat , and like his predecessors he has said Israel will not tolerate a nuclear Iran . Tests are ongoing for Israel 's arrow missile system , designed to intercept incoming rockets -- although Israel does not openly say which direction they 'd come from . Last week , CNN filmed Netanyahu aboard an F15 fighter-bomber jet while touring the Hatzerim air force base near Beersheva . He said : `` My biggest impression today is the obligation to carry out the mission of defending Israel . '' Last month , two Israeli warships and a submarine made a rare journey through Egypt 's Suez canal . Last year , the Israeli air force tested its fighter jets and helicopters on a 870-mile sortie -- roughly the distance between Israel and Iran 's main uranium enrichment plant at Natanz . The official line ... Israel 's security is a continuing concern . The common perception is that some , if not all of these exercises were a show of strength for Iran . Estimates of when Iran could have a nuclear bomb differ widely . In February , the Institute for Science and International Security released a report that concluded Iran does not have a nuclear weapon but does have enough low-enriched uranium for a single nuclear weapon . But an official at the International Atomic Energy Agency cautioned about drawing such conclusions . The U.N. nuclear watchdog agency said Iran 's stock of low-enriched uranium would have to be turned into highly enriched uranium to be weapons-grade material . The official said in February that Iran has not done so , and the agency 's monitors and surveillance equipment at the Natanz facility would be able to detect any such activity . Dore Gold , former Israeli ambassador to the United Nations said , `` The IAEA has inspected the known nuclear sites of Iran . But it 's believed they still have other clandestine nuclear sites where they may be enriching uranium or they may be pursuing a plutonium route like the North Koreans . So there 's a certain amount of uncertainty in any assessment in the timeline of an Iranian bomb . Iran says its nuclear ambitions are for peaceful means , and Israel is widely believed to have nuclear weapons itself . But Israel 's Defense Secretary Ehud Barak , at a meeting with U.S. Defense Secretary Robert Gates recently , made it clear he believes U.S. attempts at negotiations with Iran have a shelf-life . `` We clearly believe that no option should be removed from the table and this is our policy . We recommend to others to take the same position , but we can not dictate it to anyone . '' Efraim Kam , an Israeli analyst on Middle East affairs and author of `` From Terror to Nuclear Bombs : The Significance of the Iranian Threat , '' estimates that `` theoretically '' Iran could develop a nuclear bomb within the next year . But even if Israel 's conviction is correct that Iran wants a nuclear weapon and it is close to achieving that desire , does that mean it would use it against Israel ? Kam said : `` My personal view is that Iran would not do it because they understand that Israel does have a nuclear arsenal . It has to take that into account and because the U.S. will deter Iran as well . `` If you ask me , can you guarantee they will not use it , then no I ca n't . '' But that question is a step too far for Israel . It is far more concerned with what a nuclear Iran could do to the balance of the Middle East and the likely nuclear race that would follow with many of Israel 's neighbors . As Gold says : `` What is a prime minister of Israel supposed to do when he sees that threat growing to his east ? ''
Senior Israeli lawmakers have Iran top of the country 's threat list . Comment: Former diplomat says it is believed Iran still has secret sites for nuclear program . One analyst says if Iran develops nuclear bomb it does not mean they would use it .