How a U.S. Radar Station in the Negev Affects a Potential Israel-Iran Clash On a desert hilltop in the remote southwest of Israel stands a compelling argument against any notion that the Jewish state will launch an attack on Iran without the United States. The discreet complex atop Mt. Keren is a U.S. military installation, and the 100 U.S. service members who staff it are the only foreign troops stationed in Israel. Most are guards; a few are support. The technicians are recognizable by the protective suits they wear to shield them from the extraordinary amounts of radiation generated by the no less extraordinary apparatus the base is built around. The small, rectangular-shaped portable radar peeking around a concrete blast wall is so advanced it can see over the horizon, and so sensitive it can spot a softball tossed in the air from 2,900 miles away. Tehran is a mere 1,000 miles away to the northeast. On Mt. Keren, the X-band radar is indeed pointed northeast, toward Iran, where it could detect a Shahab-3 missile launched toward Israel just seconds into its flight - and six to seven minutes earlier than Israel would know from its own radar, called Green Pine. LIST: Five Tips for President Obama on Nuclear Negotiations with Iran The extra time means a great deal. Six additional minutes increases by at least 60% the time Israeli officials would have to sound sirens that will send civilians scrambling into bomb shelters. It also substantially increases the chances of launching interceptors to knock down the incoming missile before it reaches Israel, hiking the likelihood its wreckage or warhead falls in, say, the wastes of the Jordanian desert rather than Israel's heavily populated coastal plain. And should the interceptor miss, the extra time might allow for the launch of a second one. All this is possible, however, only if U.S. officials choose to share the information, because only Americans have eyes on the radar. And if it's difficult to imagine a U.S. commander-in-chief choosing to withhold an early warning that could save civilian lives of a close ally, both sides recognize that if the Iranian missiles were launched in retaliation for an Israeli air strike, the onus might be on the Israeli government that set such events in motion. In any event, military officials and outside analysts say that uncertainty can only inhibit any Israeli impulse to "go it alone." The setting of the unmarked U.S. compound, in a stretch of desert barely five miles from the Egyptian border, captures the situation. The state-of-the-art radar is tucked into a landscape buzzing with Israeli military posts and training operations. Israeli infantry drill on broken ground to either side of the road approaching the hilltop installation, which is surrounded by a chain link fence and a yellow metal gate. The guards who come out to meet visitors are plainclothes members of the Israeli Ministry of Defense agency responsible for security at Israel's most sensitive sites, including the Dimona nuclear facility to the north. MORE: Why Netanyahu's Visit to Discuss Iran Puts Obama in a Political Minefield Inside the wire, however, the chain of command is American. In the one-story building beside the radar, technically called the Army-Navy Transportable Surveillance Radar, or AN/TPY-2, the data flows first to technicians' readouts, then on to California, where the U.S. Missile Defense Agency also registers feeds from satellites and sea-borne sensors. If their computers recognize an ascending fireball as a hostile missile launch, U.S. commanders may pass the information to their Israeli counterparts. The entire system is of course built on the assumption that they will. The American and Israeli militaries have meshed their missile defense systems so snugly that they operate a joint command center, located on an Israeli military base near Tel Aviv. The Arrow interceptor missile that would be launched to knock down the attack is itself a joint-effort of the Pentagon and the Kirya, as Israeli's defense headquarters is known. Come October, some 5,000 American troops will travel to Israel for their largest joint exercise ever, one constructed entirely around missile defense. But the Israelis are keenly aware that, in this case, information is power, and Washington has the right to withhold it. "We share a lot, but there's a valve on the pipeline, and it's a one-way valve," says a Western military official involved in the program. The workaday reality of the U.S. radar - it has been operating since 2009 - also undercuts the notion of Israel launching a surprise attack on Iran that would also take Washington unawares. Not only does it see all traffic at Israeli air bases, it would certainly detect any large scale or other unusual patterns, including preparations for a massive air assault. Allowing the Americans that capability was a trade-off Israeli officials conceded only grudgingly, as TIME reported when the radar installation was announced in 2008. "It's about the United States hugging the Israelis," says an American missile expert outside of government. The intense military cooperation between Washington and Jerusalem, which both sides agree is the closest it's ever been, not only helps assure Israel's security. It also tethers Israel's military to the Pentagon. Sometimes the benefits are frankly political: When Israel's Iron Dome anti-missile system won the heart of the Israeli public by downing short-range rockets out of the Gaza Strip, sparing Israeli cities, Congress quickly authorized $200 million to purchase nine more. (MORE: What Lies? Beneath the Mysterious History of an Iranian Nuclear Site) But the X-band radar installation offers both obvious advantages and what one Israeli official termed "golden handcuffs." "It's a very sophisticated, eye-watering type of system, with a very powerful capability of precision," says the U.S. missile expert. It was an X-band radar which was used in Operation Burnt Frost when we shot down that satellite from an Aegis ship several years back that was in a low, decaying orbit. We didn't just hit a bullet with a bullet, we hit a spot on a bullet. The Negev base was outfitted and staffed by the U.S. European Command, which covers Israel. "For security reasons we can't talk too much about that gadget," says Capt. John Ross, a EUCOM spokesman. Declining a TIME reporter's request to visit the facility, the command insted issued a statement that seems calculatingly bland, at least until the final sentence: "The United States and Israel have a long-standing partnership in addressing issues of regional and global security. Consistent with our partnership and with our commitment to the security of our partners in the region and around the world, and at the request of the Government of Israel, the U.S. military has deployed a defensive radar system to Israel to help maintain regional security and provide a useful deterrent to any missile attacks. The Army Navy Transportable Surveillance Radar (or AN/TPY-2) is considered to be one of the most powerful systems available to track medium- to long-range ballistic missiles. The AN/TPY-2 will remain U.S. owned and operated. COVER STORY: Will Netanyahu Choose War or Peace?