And how will the F35 stop terrorist attacks in the UK, or car bombs in Afghanistan from getting through?
Truth is the UK is fighting an ideology of militant islam from within and external threats which are slippery and hard to determine and define. Putin is not going to wage a conventional war against NATO but he will use proxy conflicts and techniques to put pressure on HMG.
There is no political appetite left among conservatives for Cameron style military adventures abroad and a coalition under Labour is hardly going to use military force to achieve its aims.