Lord Dannatt, who was head of the Army from 2006 to 2008, writes that the Russian intervention in Ukraine and the civil war in Syria, which is an ally of Mr Putin, were “stark reminders” of how “strategic shocks” could happen in an unpredictable world. He says there is doubt as to whether a regular Army of 82,000 is sufficient for Britain’s needs, and questions whether the target of 30,000 Reservists is achievable.