Donald Trump has brought in outsiders to rapidly make dramatic cuts. Bill Clinton relied on existing government leaders to take a more targeted approach.

Elon Musk's Department of Government Efficiency (Doge) - set up to cut US government spending - claims to have saved, on average, more than $10bn a week since President Trump entered office. "We're talking about almost $200bn and rising fast," Trump told the BBC when talking about Mr Musk's cost-cutting drive on 23 April.