The main weapon in Israel’s arsenal is the US-supplied GBU-28. This is a 5,000lb (2,268kg) laser-guided weapon with a special penetrating warhead. For an assessment of its capabilities I turned to Robert Hewson, the editor of IHS Jane’s Air-Launched Weapons.

“The GBU-28,” he told me, “is the largest penetrating weapon available for a tactical aircraft and, since it was first used by the US in 1991, it has been improved with better warheads and more accurate guidance.

“However, Israel’s use of this weapon would be hindered by several key operational factors. Realistically, the F-15I – the only delivery platform – can carry only one bomb, so a sizeable attack force would be required – demanding tanker and other support assets that Israel does not have in large numbers…

“For a weapon like the GBU-28, velocity and angle of impact determine the penetrating effect, so the ideal drop is made from high altitude at maximum speed and hits the target at a near vertical angle,” he explains.

“This is less easy to do against a cave or mountainside, so the weapon will be less effective – but still more effective than pretty much any other available munitions.”

Indeed, as Douglas Barrie notes, one weapon might be insufficient.