Critics slam US 'incrementalism' in anti-IS fight

When the clock ticks down on Barack Obama's presidency, five years will have passed since he officially pulled US combat forces from Iraq.

But little by little, US troops are returning - thanks to the Islamic State group and their hold over parts of the region.

On Monday, Obama said another 250 special forces and support personnel would go to northern Syria, augmenting the 50 or so commandos already training local militias there.