
The war against ISIS has taken dramatic strides since Donald Trump became president, with the US and its allies reclaiming swathes of Iraq and Syria.

In fact, of all the land reclaimed by the US-led coalition since 2014, nearly one third has been taken since Trump took office.

That's thanks to Trump's decision to delegate decisions and engage in a 'campaign of annihilation,' Brett McGurk, the State Department's senior envoy to the anti-Islamic State coalition, told the Washington Post.

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US-led coalition troops such as the Syrian Democratic Forces (SDF; members pictured) have retaken 78 per cent of ISIS-claimed areas in Iraq and 58 per cent in Syria, with almost a third of all reclaimed areas falling since Donald Trump took office

Brett McGurk, the State Department's senior envoy to the coalition, says that Trump's 'campaign of annihilation', in which cities are surrounded to ensure militants don't escape, has helped with the wins (pictured: a US airstrike in Mosul, Iraq, in July)

Trump's decision to delegate to his military has also allowed for faster and more fluid reactions to the changing situation on the ground, McGurk - who held the same position under Obama - said

Since its peak in early 2015, ISIS has lost 78 per cent of its occupied areas in Iraq and 58 per cent in Syria.

In total, that's around 27,000 square miles of territory, 8,000 of which has been taken since February of this year.

That has almost entirely stopped civilian displacements in the countries and seen thousands of people able to return to their homes, McGurk, who had the same role under Obama, said.

ISIS has also lost around 45 per cent of its control of Raqqa, the backwater Syrian city that became its nerve center and the capital of its supposed 'Caliphate'.

Losing Raqqa altogether would strike a massive blow to the organization.

McGurk believes the continued success of the coalition is down to operational changes made by Trump.

In particular, McGurk said, the campaign has benefited from Trump's decision to hand control over to his generals.

Delegating decisions to those with more experience on the ground has allowed for faster and more fluid reactions to changes in the theater of war, McGurk said.

He also cited the 'campaign of annihilation,' which sees enemy cities surrounded before battle begins, to minimize the number that are able to escape.

McGurk believes this will result in most of the 2,000 militants remaining in Raqqa dying there when it is retaken. The city also has 25,000 civilians.

He said the new administration had also renewed efforts to 'increase burden sharing from the coalition.'

There are 73 countries in the coalition, he said, most of whom are expected to help stabilize locations that have been taken back from ISIS by US airstrikes and on-the-ground work from local allies.

ISIS has lost around 45 per cent of its nerve center, Raqqa (pictured: two SDF troops running through the city), since Trump took over. McGurk says the 2,000 remaining militants there will most likely die in the city

McGurk also stressed that the US was working to clear and rebuild basic infrastructure, but would not take part in 'nation-building' - something Trump said he was opposed to during the election.

'People say, "We want you to run the hospital, the schools,"' he said. 'We say, "No, we're not very good at that." It's not our responsibility.'

Instead, the US is focused only on making sure electricity, water, sewers and other basic necessities are functional, he said.

He added that although relations between Russia and the US have deteriorated, he has not seen 'an effect on our engagement' in the region.

There is currently a ceasefire in southwest Syria, where Russian-backed troops for the country's president, Bashar al-Assad, had run into US-backed anti-Assad armies.

While the governments of the countries are at loggerheads - particularly after the US passed further sanctions on Russia last week - their respective militaries are in communication on a daily basis, he said.