Ministers have long been concerned that a serving soldier could be targeted by terrorists, Former Home Secretary Jack Straw has said in the wake of the Woolwich attack.
In the aftermath of Wednesday's gruesome killing, Straw, who served in the Cabinet at the time of the July 7 bombings, told the Huffington Post UK he had been horrified at the "brutality" of the murder, and condemned it as "stone-age savagery".
"There has been concern about this for some time... that individual service personnel could be targeted, as they were during the IRA bombing campaign," he said.
Straw also attacked critics of plans for increased data monitoring powers.
Legislation to force internet companies to store details of online activity, dubbed a 'snooper's charter' was shelved after pressure from the Liberal Democrats.
There have now been calls for the Bill to be revived.
Straw said: "This raises the issue about increased communication data. We do not know at this stage that the absence of these powers was a factor in their being at large.
"I hope the Intelligence and Security Committee will look at it."
He added: "No doubt the same people describing it as a snooper's charter will be saying 'why didn't the security services pick them up'?"
The fact that the men were known to the security services did not mean they should have been picked up, he added.
The Blackburn MP warned of a "very present danger" of a backlash against British Muslims.
And he criticised Home Secretary Theresa May's decision to scrap controversial control orders for terror suspects and replace them with 'TPims', which restrict the movement of people who cannot be formally tried.
"I think that was daft, and I think they regret that now. It was a hangover from irresponsible opposition," he added.