The carnage at the Boston Marathon bombings last month and the savage butchering of a solider on a London street just over a month later demonstrate that fanatical Muslims may be heeding terrorist groups' calls for individually organised attacks against Westerns.
Internet sites urging radicals to carry out their own jihadist strikes are seen by intelligence analysts as a new tool in terrorists' arsenal after worldwide security clampdowns following the attacks in the United States in 2001 and later in many other countries, most notably Indonesia, Spain and London.
The internet magazine Inspire, said to be published by Al Qaeda in the Arabian Peninsula, was where there US authorities believe the Tsarnaev brothers found the expertise to construct bombs using everyday materials -- pressure cookers, fireworks, nails -- that they detonated close to the finish line of the Boston Marathon, killing three people and injuring more than 280.
If that's not enough to goad militants into action against Westerners, some Muslim clerics in the Middle East are openly calling for their acolytes to attack -- in speeches in mosques that are filmed and posted on YouTube for the faithful to view around the world. Earlier this year a Muslim cleric in Saudi Arabia, Muhammad bin Nasser Al-Suhaybani, said Muslims must attack Westerns for insulting the prophet Muhammad.
"By Allah, on this matter we pray to Allah to put an end to the evil of these infidels. [As it says in Koran 2:217:] 'They will not cease to fight you until they force you to renounce your faith.' However, Allah the Exalted made it clear that we must have zeal... 'But, if after coming to terms with you, they break their oaths and revile your faith, make war on the leaders of unbelief - for no oaths are binding with them -- so that they may desist," he said.
The sole surviving Tsarnaev brother, Dzhokhar, after his sibling, Tamerlan, was gunned down in a police shootout, has allegedly told investigators that they carried out their bombings to avenge the killings of Muslims in Afghanistan as the US and its allies continue to wage war against the Taliban.
Yesterday, after brutally murdering a solider who was walking along a street in the hitherto somnolent London street of Woolwich -- apparently decapitating their victim -- the two perpetrators did not flee but strutted about seeking attention, speaking to anyone holding aloft a phone and taking pictures of video. It was not enough to kill in cold blood; they wanted the world to know what they had done, even if it cost them their own lives. Acts of terrorism -- which the government of Prime Minister David Cameron said this most likely was -- are most effective with a media presence.
His hands soaked in fresh blood and carrying a knife, one of the men told a courageous woman who had jumped off a passing bus to try and aid the victim but ended up confronting the attacker: "I killed him because he killed Muslims and I am fed up with people killing Muslims in Afghanistan..." It was, he said, a case of "an eye for an eye."
Indeed, early accounts from the police indicate that the two men, far from escaping the scene, then set their sights on the police in what seems a kind of martyrdom attempt, and ended up being shot but not killed.
As people in London reeled from the horror of the barbaric attack, a realisation was setting in: Is this a new wave of terrorist attacks, and what can be done to stop it? The answer to that is, very little. The weapons the terrorists are now employing are everyday items that are in everyone's homes and therefore impossible to police. Any would-be attacker with enough gumption will get past any kind of security and carry out their act. Even intense security measures are no guarantee against bombings.
After the luxury JW Marriott hotel was car-bombed in the Indonesian capital of Jakarta in 2003, killing a dozen people, airport-style metal detectors were installed at the property's entrance, and I said to myself one evening as I walked through them that this place was as secure as a fortress and would never again be attacked. Six years later two suicide bombers checked in and blew themselves up, killing seven people.
The lasting solution to tackling the plague of Islamic terrorism lies not in overtly heightening security measures and therefore infringing on citizens' freedoms but to cutting off the radical call to arms at its source. That means engaging the authorities in countries where they originate and working out ways to do so, including drawing up and enacting relevant legislation in the host countries.
Monitoring mosques is the obvious starting point. As long as influential Muslim leaders keep fostering a culture in which the death of Westerners is a desired goal, the attacks will continue, and no amount of security can thwart them all.
Follow William J. Furney on Twitter: www.twitter.com/wmfurney