They dismiss life as merely a means to notoriety. Infamy is worth a life or several or even many. The actions of the loner-simpleton, the deranged "pathetic social misfit" tag attributed by the courts to Port Arthur gunman Martin Bryan is a case study. Pathetic, deplorable, but conceivable or understandable.

The political or religious lone wolf terrorist always involves a pyschopathic factor. Delusional, moral justification for civilian slaughter. Sadly such depraved acts have wider, catastrophic ramifications.

When Gavrilo Princip assassinated Austrian Archduke Franz Ferdinand 100 years ago this June it cascaded into World War I.

Lee Harvey Oswald's assassination of US president John F. Kennedy in 1963 indirectly plunged America into the Vietnam conflict lasting 10 years and costing about 50,000 military lives. President Kennedy was wary of Vietnam. His vice president Lyndon Johnson who assumed the mantle, was hell bent on massive involvement.

But you can comprehend the deranged bid for notoriety by Bryant, or Mark Chapman who shot John Lennon in 1980 or John Hinkley who almost succeeded in assassinating President Ronald Reagan in 1981.

It's when the lone wolf - the home-grown drones of Isis - mix political goals with civilian targets, that it gets awful and despicable.

December is roughly the start of the Judeo Christian festival of Christmas and Christ's birth, or, alternatively a time of shopping, Santa Claus and thanks giving practices among agnostics. It is the equivalent of the Islamic Ramadan period on the cultural calender. A time when the Western civilian population winds down to take a breather; become family focused and deliriously festive.

It was the perfect time for the Sydney zealot to strike, in a small cafe on Australia's most famous boulevard.

We have our own world of freedom of action and expression, which we hold dear. No doubt other faiths like Islam and Buddhism enjoy our festive period because adherents live here.

It's part of our culture to enjoy and share in a relatively harmonious multicultural existence.

A deranged eccentric like Man Haron Monis knew this when he twisted the Koran to suit his purpose in Martin Place on Monday.

Like the Taliban, Isis and other terrorist groups the strategy is to cast civilians as soft targets for shock propaganda value. Defenceless, unaware souls; peace loving, passive and pre-occupied with life. Just like the 200 school girls kidnapped and sold in Nigeria.

Such extremism and adventure is a magnet for some Islamic youth. It allows them or their mentors to adopt medieval religious pronouncements and twist them into modern criminal solutions.

We view them in vain as an opportunity for reconciliation. They view us uncompromisingly as grounds for genocide.

Thankfully the vast majority of Muslims in the Middle East want to live peacefully, even if there is religious or ideological disagreement. The task for the West is not only to destroy terrorism militarily but also to destroy its appeal and expose it as an affront to all religions and cultures.

It is costing Australia a small fortune, about $30 billion for Iraq and Afghanistan and about $500 million a day for the current war on Isis, but it's worth it. If we don't win this war expect lots more Bali Bombings and Martin Place sieges.

Don't for a moment think they'll stop if we do. Their methods are based on a bigoted dogma, not a protest.