There is one phrase that has stood out for me over the last few days. One jarring, horrible sentence that betrays the warped mindset of many on the Left when it comes to Islamic extremism: “What happened on Wednesday was terrible, but...”

We have heard it, and its variations, from almost all of the usual suspects since the Woolwich terror attack. Ken Livingstone gave a long condemnation of the terrorists on Friday, only to try to blame Tony Blair and the Iraq War for what happened.

Glenn Greenwald, very careful to thrust the words “horrific act of violence” into the first line of his utterly disturbing piece for the Guardian, compares the killing of a British soldier in London by terrorists to the killing of terrorists in the Middle East by western forces as like for like.

I had lunch with another Guardian journalist who believed this was just another murder on the mean streets of our capital; that the murder of a Muslim by racist white Britons is equally newsworthy.

Owen Jones, meanwhile, seems determined to draw attention away from Woolwich, away from Islamists, and towards the English Defence League (EDL). He would have us believe they were the real, dangerous evil here.

I find it incredibly sad that these four leading voices of the left - no doubt all intelligent men - would discard all semblance of rationality, particularly at such a sensitive time.

Livingstone ignores the fact that Al-Muhajiroun, the extremist group linked to Michael Adebolajo, and its offshoots have been peddling its evil long before Iraq and many other Western interventions in the Muslim world and has recently been shown to be connected to 18 per cent of convicted Islamic terrorists between 1998 and 2010. To attribute blame to Western foreign policy is as intellectually vacuous as it is offensive.

Greenwald’s equating of British soldiers to Islamist terrorists is even more repugnant. Of course the Left - and the Right for that matter - have legitimate criticisms over foreign policy, but to become so blinded by self-loathing that he blurs the distinction between good and evil, for me, makes Greenwald an apologist for terror.

My Guardian journalist lunch partner inspired gasps around the table with his own comparison of the attack to “any other murder”. How he fails to grasp that the unprecedented killing of a British soldier by an Islamist terrorist in London is of greater news value than a “normal” murder perhaps explains why he works for the newspaper he does.

As for Owen Jones, there is something utterly odd in obsessing with the EDL in the way he has. English nationalism is a weak ideology with few supporters that is powerless on the world stage, and pretty impotent even at home. Islamic extremism is arguably the greatest evil faced by the free world. The EDL is nothing; why even give them the time of day?

There is a sickness in the hard Left. Their unerring, almost sociopathic desire to direct the blame for terrible events onto our own country, our own ideology, our own people, is beneath contempt. Sometimes it is enough to just say “this was awful, this was evil, we will not waver”.

By attacking our own, the Left is doing exactly what the terrorists wanted all along. As a result, they have become the useless idiots who encourage the status quo.

Alex Wickham is The Commentator's UK Political Editor and a reporter at the Guido Fawkes website. He tweets at @WikiGuido