Nuclear facilities as military targets? The drumbeat appears to be growing louder. Western leaders repeatedly declare that no option is off the table to stem Iran’s nuclear ambitions. And, in mid-November, London’s Sunday Times reported that Israel put defences around its Dimona nuclear reactor on “red alert” 30 times, as worries grew that Syria would avenge Israel’s September attack on a suspected nuclear site in Syria.Israel’s fear reflects the region’s unique history. Since World War II, strikes to halt nuclear activities have taken place exclusively in the Middle East: Iraq was struck by Iran (1980), Israel (1981), and the United States (1991, 2003), while Iraq bombed Iran (1984-87) and Israel (1991). But raids never generated significant radiological consequences, because plants were under construction, contained inconsequential amounts of nuclear material, had radioactive elements removed prior to the attack, or because the attacker missed the mark.A successful strike on Dimona, however, would be another matter. So, given the threat of radioactive releases, does the plant’s continued operation outweigh the risks?Dimona is unique. It is the region’s largest nuclear plant and sole producer of atomic weapons materials. Since it went into operation in the mid-1960s, it has generated elements for an estimated 200 nuclear weapons. Israel’s first prime minister, David Ben Gurion, inaugurated the enterprise to compensate for Israel’s strategic vulnerability, a fledgling army, and the West’s unwillingness to enter into a formal alliance to defend the Jewish state.Dimona is no Chernobyl. It generates only about 5 percent of that failed Soviet reactor’s power. Still, the plant — along with its spent nuclear fuel, extracted plutonium, and nuclear reprocessing waste — poses significant radiological hazards that a military strike could disperse into the environment.Israeli officials tacitly acknowledge the risk. Authorities have distributed potassium iodide tablets to the nearby towns of Yerham, Dimona, and Aruar. Potassium iodide blocks thyroid absorption of radioactive iodine, an early risk in a nuclear release. But it would not obstruct serious health consequences from other radioactive elements. And, depending on weather and the nuclear discharge, the radioactive consequences may not remain localised.Light contamination and hot spots could impact Israeli, Palestinian, and Jordanian urban centres some distance away. Beyond health effects, contamination could terrorise affected populations, prompting temporary flight and permanent relocation. Serious, long-term economic consequences would follow.For decades, Israel dealt with this risk through effective air defences and disdain for its adversaries’ ability to strike Dimona. In May 1984, after I authored a book about the consequences of military attacks on nuclear facilities, an Israeli intelligence officer came to California to question me about the vulnerability of the reactor and a proposed nuclear power plant. The officer belittled the risk, arguing that no Arab air force had ever overcome Israeli air defences, and none ever would.At that time, history provided odd support. Although Egyptian reconnaissance aircraft had flown near Dimona in 1965 and 1967 without incident, during the 1967 war, Israel shot down one of its own Mirage jet fighters when it strayed over the facility. In 1973, Dimona’s defenders downed a wayward Libyan civilian airliner heading for the reactor, killing 108 people.But the 1991 Persian Gulf War upset whatever solace Israel could take from the past. Iraqi Scud missiles bombarded Tel Aviv, and one came close to hitting Dimona. Hezbollah’s bombardment of northern Israel in 2006 further demonstrated the country’s vulnerability to missile attack. And, while Israel’s Arrow ballistic missile defences, which now surround Dimona, may be superior to the Patriot system that failed in 1991, Syria’s more advanced Scuds and Iran’s Shahab-3 rocket present a more capable challenge than Saddam’s projectiles.Dimona has produced all the plutonium that Israel reasonably needs, and the reactor — one of the world’s oldest — has suffered minor mishaps and evident deterioration, raising the spectre of more serious accidents. So, if Israel cannot guarantee the plant’s defence against attack, it should close it.By doing so, Israel could also derive political benefits. It could claim that closure demonstrates its commitment to reducing regional nuclear tensions, while sending a message about the wisdom of building reactors in the world’s most volatile region.Indeed, about a dozen Middle East and North African countries propose to build nuclear power plants. Given the historic targeting of atomic installations, planners should consider whether providing adversaries with radiological targets far larger than Dimona makes sense. Until the Middle East resolves its political differences, it may not. —DT-PS Bennett Ramberg, served in the Bureau of Politico-Military Affairs in the George H W Bush Administration. He is the author of several books on international security