Boris Johnson has said that it should be assumed British citizens returning from Iraq or Syria have been involved in terrorist activities unless they can prove otherwise.
In his Daily Telegraph column, the Mayor of London wrote: "The law needs a swift and minor change so that there is a 'rebuttable presumption' that all those visiting war areas without notifying the authorities have done so for a terrorist purpose." He adds: "There are perhaps five or six hundred Britons currently out there – overwhelmingly, though not exclusively, young men. If and when there is a real attempt to take on Isil, they may come back in a hurry and in a group."
Johnson also advocates the return of control orders, which were introduced in 2005 and repealed in 2011. These allowed the home secretary to restrict an individual's liberty on command, perhaps demanding a suspect surrender his passport and placing restrictions on visitors. They have been described as a "prison without bars".
On the wider question of intervention, Johnson is non-committal. He writes:
"These Isil wackos now control an area the size of Great Britain, considerable oil reserves, a population of about six million, some industry, and a military capability said to be second in the region only to Israel. To take them on will not be easy, and I can see all the arguments for doing little or nothing – letting “history” take its course. No one could claim that previous Western operations have been crowned with success. It is now pretty obvious to everyone (except the bonkers Tony Blair) that things were made much worse, not better, by the removal of Saddam Hussein. How can we be sure of doing better this time?
. . .
No option looks very appealing, to put it mildly; and yet doing nothing is surely the worst of all. If we let Isil get their way, then we will be acquiescing, first, in a gigantic and violent change in international borders. Next, we will be allowing a new and hideous regime to be born: a country where black-flag waving jihadis compete to show they have the most bigoted and reactionary understanding of their religion by persecuting women, Jews, Christians, gays, Yazidis and Shi’ites."
Johnson's comments will renew pressure on foreign secretary Philip Hammond to announce further measures to combat extremism in Britain and terror abroad, following the execution of journalist James Foley by a militant with a British accent. Last week, Hammond ruled out the option of co-operating with Syria's Bashar al-Assad to fight the jihadis of Islamic State (also known as Isis).