Much of Egyptian President Sisi’s claim on Western support rests on his promise that he can maintain his country as an island of stability in an otherwise turbulent Arab world, and on his successful crushing of terrorist groups. If terrorists linked to Islamic State did in fact bring down a Russian airliner (as now seems likely), Sisi’s argument may be headed for trouble, as Oren Kessler writes:

The air disaster has overshadowed what was supposed to be a public-relations coup for Sisi: an official visit to the residence of British Prime Minister David Cameron, where talk of a shared counterterror vision and investment in Egyptian energy was to replace reports of mass arrests, death sentences, curtailed freedom of speech, and the heavy-handed response to the Sinai unrest. Instead, the visit has been dominated by questions of security in Egypt, the costs of doing business in the country, and the wisdom of keeping its air routes open.

Despite his government’s excesses, Sisi’s inner circle insists that his commitment to counterterrorism in a dangerous environment is reason enough to merit international support. It’s not a baseless argument—the world’s most unstable region is engulfed in unprecedented volatility, and Egypt is both the largest Arab state and a decades-long Western ally. Still, the possibility that on his watch Egypt suffered its worst-ever terror attack has called into question the president’s counterterrorism tactics. If Sisi’s uncompromising methods can’t prevent a brazen, mass-casualty attack, Western policymakers will inevitably wonder what purpose they have served.

On Tuesday, a Hizballah drone attack injured three people in northern Israel. The next day, another attack, targeting an IDF base, injured eighteen people, six of them seriously, in Arab al-Amshe, also in the north. This second attack involved the simultaneous use of drones carrying explosives and guided antitank missiles. In both cases, the defensive systems that performed so successfully last weekend failed to stop the drones and missiles. Ron Ben-Yishai has a straightforward explanation as to why: the Lebanon-backed terrorist group is getting better at evading Israel defenses. He explains the three basis systems used to pilot these unmanned aircraft, and their practical effects:

These systems allow drones to act similarly to fighter jets, using “dead zones”—areas not visible to radar or other optical detection—to approach targets. They fly low initially, then ascend just before crashing and detonating on the target. The terrain of southern Lebanon is particularly conducive to such attacks.

But this requires skills that the terror group has honed over months of fighting against Israel. The latest attacks involved a large drone capable of carrying over 50 kg (110 lbs.) of explosives. The terrorists have likely analyzed Israel’s alert and interception systems, recognizing that shooting down their drones requires early detection to allow sufficient time for launching interceptors.

The IDF tries to detect any incoming drones on its radar, as it had done prior to the war. Despite Hizballah’s learning curve, the IDF’s technological edge offers an advantage. However, the military must recognize that any measure it takes is quickly observed and analyzed, and even the most effective defenses can be incomplete. The terrain near the Lebanon-Israel border continues to pose a challenge, necessitating technological solutions and significant financial investment.