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
A shock to the system
We found a tableau of desperation; vast crowds of people pushing and shoving their way forward, away from the continuing bombardment.
Cambridge Analytica played a key role in mapping behaviour of voters in the US election and was used during the EU referendum campaign.