On May 14, 1940, a swarm of Nazi warplanes darkened the skies over Rotterdam, sowing flames, terror and destruction. Within hours, the Dutch government capitulated to Hitler.

Just as some prewar military theorists had predicted, a new wonder weapon, the strategic bomber, had made ground combat virtually unnecessary.

Ever since, strategists have tried to win wars with airpower alone . But overconfidence in air strikes can be a “dangerous delusion,” Michael Beschloss warned in The Times Book Review.

Reviewing “The Age of Airpower, ” by Martin van Creveld, Mr. Beschloss wrote: “I hope that this spring, van Creveld’s timely book will remind NATO leaders supervising the bombing campaign in the Libyan civil war of how often in history we have watched air power lead unexpectedly to ground fighting on quicksand.”

Indeed, after Rotterdam, the wholesale devastation of cities during World War II mostly seemed to galvanize the will of nations to fight on, at least until the nuclear attacks on Japan. And the American carpet bombing in Vietnam failed to dislodge a determined guerrilla foe. But air power has had success: NATO bombing raids in 1995 compelled the Serbs to negotiate for peace.

High-tech weapons remain a seductive and seemingly risk-free choice for policy makers. Long-range cruise missiles and pilotless drones can be controlled from secure bunkers or ships thousands of kilometers away and strike with surgical precision.

But the surgery can still get bloody and messy. Recently, the troubled alliance between Washington and Islamabad ruptured over a demand that America end its drone strikes on militants in the tribal regions. A key reason was civilian deaths from the attacks.

Removing the risk of human casualties could change the face of ground combat as well. Walking, rolling and crawling robots equipped with sensors and weapons are in the planning stages. Some experts believe they will revolutionize armies by allowing their operators to attack from a safe distance.

But as John Markoff wrote in The Times, “Opponents say that robot warriors lower the barriers to warfare, potentially making nations more trigger-happy and leading to a new technological arms race.”

However, most wonder weapons are eventually countered by other wonder weapons. And all those sophisticated armaments linked to computer networks may yet prove vulnerable.

Last year, Stuxnet, a malicious computer worm likely developed by Israeli and American programmers, disabled the gas centrifuges crucial to Iran’s nuclear arms program, The Times reported.

Similar weapons could be used against more technologically advanced nations to disable anything linked to a network, including weapons and infrastructure, without firing a shot.

In his book “Cyber War: The Next Threat to National Security and What to Do About It,” Richard A. Clarke, the former American counterterrorism czar, warns of “a massive cyberattack ... that smacks down power grids for weeks, halts trains, grounds aircraft, explodes pipelines and sets fire to refineries.’’

Mr. Clarke calls it an “electronic Pearl Harbor.”

But if the cyberattack left a nation too paralyzed and terrorized to even contemplate fighting back, an “electronic Rotterdam” could prove a more fitting analogy.


KEVIN DELANEY