Monday's terrorist attack in Britain's third-largest city, Manchester, marks a new low, even for Islamic State. The target was an Ariana Grande concert whose audience was largely teenagers and pre-teens with their parents. In the twisted minds of Islamic State followers, not even children should be spared maiming and death.

Forget trying to make sense of an insane ideology. It's not about righting the historic wrongs of the Middle East, nor about winning over converts. It's about deliberately inflicting shock and horror. It's about brainwashing devotees into thinking they can please God through ever-escalating acts of carnage.

"These were children, young people, and their families. Those responsible chose to terrorize and kill. This was an evil act," Manchester Mayor Andy Burnham told reporters.

The timing seems hardly coincidental, occurring only a day after President Donald Trump concluded a high-profile visit to Saudi Arabia where his keynote speech focused on the requirement of Muslim leaders to confront the evil in their midst.

Britain already was on its second-highest state of alert. The non-Muslim world can only do so much to harden its defenses against suicidal fanatics. The leaders of Muslim nations, along with clerics, grade-school teachers, professors, television personalities — anyone with influence — must do better at hammering home the message that violent fanaticism is the way of evil, not Islam.

No country, including America, can protect itself by banning Muslim immigration and sealing the borders while adopting an us-versus-them mentality. The "us" in this case includes Muslims, Christians, Jews, atheists and agnostics bonded by a common respect for the sanctity of human life. The "them," as is evident from terrorist attacks in New York, Boston, San Bernardino, London, Paris, Nice, among many others, are deranged individuals who draw inspiration from online videos and chat rooms.

Diverting them from a murderous path requires equipping them with the philosophical tools to resist when they are bombarded by propaganda. Saudi Arabia's new Global Center for Combating Extremist Ideology might help, but glowing orbs are no match for the ongoing messages of extremism propagated by the kingdom's own Wahhabi clerics.

Sadly, the West could be girding for a new wave of harsh public security responses similar to the ones that followed the Sept. 11, 2001, attacks, when airliners had to be refitted with hardened cockpit doors, and passengers began having to partially disrobe at security checkpoints. The Trump administration now proposes banning laptops from international flights.

What next for public gathering places? The Manchester attack, like those that preceded it, suggest no venue is safe anymore. Cars or trucks plowing through packed crowds are the new weapons of mass destruction.

A society that hunkers down in fear, sacrificing ever-increasing bits of freedom in the name of public security, is one that already has handed victory to our enemies.

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