Vladimir Putin made the decision to invade Ukraine - sending shockwaves around the world. As Russian forces have shelled schools, administrative buildings and residential blocks, civilians on both sides have expressed horror at the sudden turn of events. As detention centers in Moscow and St Petersburg fill up with detained anti-war protesters, the casualties in Ukraine - and among the Russian Armed Forces - is beginning to grow. The EU, which until recently was accused of being divided and unable to respond cohesively to the threat, has sprung into action, imposing sanctions on oligarchs and cutting off Russia and its banking institutions from global finance. Even neutral Switzerland is freezing Russian assets, and Germany suddenly transformed its defence policy overnight - with Chancellor Olaf Scholz announcing a more than $100 billion fund to modernize Germany's defense forces. For now, Ukraine is holding off advancing forces - but things may change. Former Chief of MI6 Sir Richard Dearlove considers Putin's options, and how the West ought to respond.