As China holds military drills to deter what it calls separatist and 'external' forces, Taiwan worries that it is a sign that an invasion could be held in the next few years. It comes after the US signed a historic $11 billion arms deal with Taipei. It's the second year where these drills include a blockade scenario, 'but it's the first time they're aimed at deterrence' says Una Aleksandra Berzina-Cerenkova, Head of Riga Stardings University China Studies Centre in Riga, Latvia.