As the Islamic State faces military defeat and begins to fragment, more and more British fighters, medics and jihadi brides will die desperately defending its territory.
Others will try to escape Syria and Iraq seeking sanctuary in Turkey where more than 50 British jihadists and their families are already believed to be holed up, stuck in a kind of legal limbo.
In the last two weeks alone one Manchester fighter and two medics have died defending the terror state against overwhelming forces.
Jamal al-Harith, a British fighter who had been released from the US detention camp at Guantanamo Bay in 2004, was killed when he carried out a suicide car bombing at an Iraqi army base in Tal Gaysum, southwest of Mosul.
Days later, two British medical students who had joined Islamic State in 2015 were also killed during fighting in Iraq. Ahmed Sami Khider, from London, and Hisham Fadlallah, originally from Nottinghamshire, are thought to have been killed after a convoy attempting to leave Mosul came under attack.
Only now can we see that death is the ultimate price to be paid for joining Islamic State and the shocking scale of the British Muslim involvement in the conflict.
The threat to Britain is perhaps graver than ever as determined terrorists fleeing Syria seek to wreak revenge on the West.
This week the UK’s newly appointed terror law watchdog warned of that threat to the UK.
Max Hill QC, the independent reviewer of anti-terrorism legislation, said IS was planning “indiscriminate attacks on innocent civilians” on a scale similar to those perpetrated by the IRA 40 years ago. He said that Islamists were targeting UK cities and said there was an “enormous ongoing risk which none of us can ignore”.
Britain’s security services estimate that around 850 UK citizens, mostly fighters, have travelled to Syria and Iraq to take part in a violent jihad. Other estimates put the figure as high as 2,000.
Across Europe the official figures for foreign fighter is estimated to be well over 5,000. Paris and Brussels have already felt the full force of terror atrocities organised from inside Syria and using returning fighters to indiscriminately kill scores of civilians.
Britain’s security services, MI5 and MI6, believe an attack on the UK is highly likely, especially as the Islamic State and other terror groups fighting in Syria start to fragment and fighters leave the region.
Max Hill says: “It’s an enormous concern that large numbers – we know this means at least hundreds of British citizens who have left this country in order to fight – are now returning or may be about to return.”
These fears are echoed by the Metropolitan Police Force’s former head of counter terrorism. Richard Walton, who led the Met’s anti-terror command until his retirement last year, warned this week that the danger of a marauding firearms attack in the capital was a “constant anxiety”’ to police and the intelligence services.
The arresting presence of Robocop-style armed police officers on the streets of London will no doubt reassure the public that the Government is doing all it can to combat the threat of terrorism. But the recently retired Met Commissioner Sir Bernard Hogan-Howe warned last year that it is a question of when, rather than if, attacks like those witnessed in France and Belgium will be visited on Britain.