With manned aircraft, carriers are not a cost-effective way to counter insurgents and terrorists, and will face budget cuts in order to fund other, less costly sources of airpower.
These include closer co-operation between national intelligence agencies, the creation of an EU counter-terrorism chief, and measures that make it easier to trace terrorists who use mobile phones and e-mail.
Counter-terrorism officers say muscular powers of arrest enable them to disrupt terrorists' networks and their plans to attack, even when there is insufficient evidence to convict them.