During the Napoleonic Wars, when it was reported that the French were preparing to invade England, Admiral John Jervis said “I do not say they the French cannot come–I only say they cannot come by sea.” Barring the movement of a regiment of sans culottes across the English Channel by a fleet of Montgolfier balloons, the Jervis comment pretty much summed up the limits to French ambitions as long as Britannia ruled the waves.

A similar bit of military overreach appears to be surrounding the alleged planning by the Israelis to stage an air assault on Iran’s nuclear facilities. The US media and even some Pentagon spokesmen have suggested that Israel cannot do the job alone, but the problem is much larger than that, leading to the question whether Israel can do it at all. Israel has over 400 fighters, but many of them are configured to establish air superiority over an opponent by shooting down opposing aircraft and disabling air defense facilities on the ground. They are fighters supporting ground operations first with a limited secondary capability as bombers.

Israel has no dedicated bomber force but it does have an estimated 125 advanced F-15I and F-16I’s, which have been further enhanced through special avionics installed by the Israel Aircraft Industry to improve performance over the types of terrain and weather conditions prevailing in the Middle East. The planes are able to fly long range missions and very capable in a bombing role but they do have their limitations.

It is generally agreed that any attempt to destroy the hardened and well-defended Iranian nuclear sites would require use of the United States-provided GBU-28, a five thousand-pound laser-guided smart bomb that can be directed to the target. The GBU-28 is regarded as accurate and able to penetrate deep into a target, which is why it has been described as the “bunker buster.” Exact performance specifications of the weapon are classified, but it is believed to be able to penetrate twenty feet of reinforced concrete. Whether that would be enough to take out the expected Iranian targets at the research centers in Natanz and Fordow, the heavy water facility at Arak, and the operating reactor at Bushehr is unknown and some analysts have opined that it might require multiple hits on the same spot to do the job. As Bushehr, the most accessible target of the three, is an active reactor, an attack would release considerable contamination.

Assuming that the US has supplied Israel with a sufficient supply of GBU-28s to go around to all the available aircraft, there remain two additional problems with the weapon that impact Israeli ability to stage an attack. First, it is so heavy that only Israel’s twenty-five F15Is are able to carry it, one bomb for each plane. For optimum use against a target, the GBU-28 also requires a clear line of sight, which means that the plane has to be flying low and relatively slowly, making the fighters more vulnerable to ground defenses, particularly with their maneuverability limited due to the bomb load. This first problem creates the second problem, which is that an attack will require a separate fleet of F-16 fighters unencumbered by GBU-28s to go in first and suppress the defensive fire, further complicating the mission.

Assuming that all the Israeli fighters capable of carrying the GBU-28 are available, which would not normally be the case, twenty-five bombs might not be enough to do critical damage to the targets. Perfect intelligence is required to place the bombs where they will do the most harm, an element that will likely be lacking with the underground targets. Some bombs will miss while others might not function perfectly and will detonate before penetration. And before the bombs are dropped the planes have to arrive over Iran.

Let’s assume that the Israelis opt for an attacking force of 50 fighters, one third of which would be designated for suppression of ground fire. The planes would be equipped with conformal fuel tanks built into the fuselages for extended range. They would also have auxiliary tanks that could be jettisoned when empty. Nevertheless, the attacking force would have to take off from Israeli airfields and then almost immediately refuel either over Israel or above the Mediterranean because fighters burn considerable fuel in getting off the ground. Refueling from Israel’s twelve modified Boeing 707 and C-130 tankers would take some time even though a plane using a flying boom for refueling can top up in thirty seconds. It is the maneuvering and connecting to enable the refueling that takes considerably longer. Refueling all 50 planes will be a major task essential to the success of the mission and while the planes are in the air and forming up they will be detected by radar in Egypt and Lebanon, information that one must assume is likely to be shared with Iran.

The objectives in Iran are more than 1,000 miles from Israel and the planes must be able to spend some time over their targets, which is why the refueling is necessary. But even then there would be problems if the Israeli jets have to engage any enemy planes either en route or over Iran. They would have to drop their auxiliary tanks to take defensive action and would probably have to return immediately to Israel.

There are three possible routes to Iran. One route to the south violates Saudi airspace and it is by no means certain that the very capable 80 plus F-15s of the Saudi Air Force would not scramble to intercept. The other is to the north over Syria, skirting the Turkish border. Syria is unlikely to be able to interfere much given its current troubles though it does possess some capable Russian made anti-aircraft missiles, but a Turkish response to possible airspace violations cannot be ruled out. The third and most likely option is to fly along Syria’s southern border, avoiding Jordan, and then through Iraq, which has only limited air defense capabilities since the US military’s departure at the end of 2011.

Israel’s previous attacks on nuclear facilities in Iraq and Syria hit targets that were above ground while relying on the element of complete surprise. Upon arrival over Iran, the Israelis would be confronted by something quite different, targets that are deep underground or hardened with reinforced concrete and further protected by layers of ground defenses that will be alert and waiting. Iran is known to have batteries of Russian supplied SA-5s for high altitude targets and SA-15s for lower level attackers. Both systems are regarded as very effective. It has also been alleged that Tehran has been able to acquire advanced Russian S-300 long range missiles, which, if true, would pose a serious problem for the Israeli fighters. The Israelis would have to be very lucky to avoid losses.

Assuming that the Israeli Air Force is able to carry out the refueling, fly successfully to Iran, suppress ground defenses, and carry out its bombing, it still has to return home, again flying over Iraq with every air force and air defense battery in the region on full alert. Depending on how much maneuvering was required while over Iran, some planes might well need to be refueled again which would mean deploying highly vulnerable tankers over Iraq or Jordan.

Back at home the Israelis would have to expect volleys of missiles of all kinds and varieties launched by Hezbollah in Lebanon to retaliate for the attack. The US-funded Iron Dome defense missile system would intercept many of the incoming missiles, but some would certainly get through and Israeli civilian casualties could be high.

It is clear that staging the attack on Iran would be fraught with difficulties and intelligence estimates suggest that at best the bombing would set back the Iranian ability to construct a weapon by only a year or two. Plus the attack would make certain that Iran would pursue a weapon, if only for self-defense, an essentially political decision that has not yet been made by the country’s leadership.

Israel has other military assets–including ballistic missiles and submarine-launched cruise missiles–that could be used to attack Iran, that would invite retaliation from Iran’s own ballistic and cruise missiles, considerably complicating post-attack developments. There is also the Israeli nuclear weapons capability, use of which would invite worldwide condemnation and instantly escalate the fighting into a regional or even broader conflict.

On balance, all of the above suggests that the frequently repeated threat by the Israeli leadership to attack Iran is not a serious plan to take out Iran’s nuclear sites. It is more likely a long running disinformation operation to somehow convince the United States to do the job or a deliberate conditioning of the Israeli and US publics to be supportive if some incident can be arranged to trigger an armed conflict. If one believes the two presidential candidates based on what they said in Monday’s debate, both have more-or-less conceded the point, agreeing that they would support militarily any Israeli attack on Iran. Whether Romney or Obama is actually willing to start a major new war in the Middle East is, of course, impossible to discern.

Philip Giraldi, a former CIA officer, is executive director of the Council for the National Interest.