US generals 'could not disobey' Trump's orders

The US Republican candidate Donald Trump recently made a controversial call for terrorists' families to be targeted by the military.

He's since softened his stance - but former head of the CIA Michael Hayden recently said US forces could simply refuse to obey his orders.

William Perry - who was Defence Secretary in the Clinton administration - told Martha Kearney that was not how the American system of government worked.

(Photo: Donald Trump speaks at a campaign rally Sacramento, California on June the first. Credit: Getty Images)