The British Army could take up to two years to get back to normal after stepping in to cover the shortfall in Olympic security.
Speaking to The Guardian the military's chief planner for London 2012 said 18,000 troops were deployed - many at short notice and diverted from their usual duties.
Wing Commander Peter Daulby also warned that reducing the size of the military could put Britain at risk of not coping with civil emergencies.
More top news
Prince Harry received a great big hug from four-year-old Carson Hartley.
The mother of "bucket list" cancer patient Stephen Sutton has said signs of her son's illness were "ignored".
Boxing champion and occasional actor Mike Tyson has been praised for coming to the aid of a motorcyclist injured in a crash in Las Vegas.