Michael Portillo (a hugely experienced former Conservative Defence Minister)
Was Def Sec for under two years, before which he was Employment Sec (one year) and Chief Sec to Treasury (two years).
Experienced, yes, but not hugely.
Portillo and Abbot are agreeing on what is very evident - we are spending far more than we can afford, and even if we cut defence spending to zero (ie stop paying all Armed Forces uniformed and civ employees, and stopped buying anything for Defence) we'd still be spending more than taxation is raising.