Ex-Diplomat: US Elites Alarmed That Trump May Accomplish Promised Foreign Policy

"Terror has again gripped the establishment that the Trump who was elected president in 2016 might actually start implementing what he promised," Jatras, who was also once a US Senate foreign policy adviser, said on Thursday.

Trump needed to also overhaul the rest of his top-tier defense and national security advisers and chiefs, Jatras said.

"This will be a critical time for the Trump presidency. If he can get the machinery of the Executive Branch to implement his decision to withdraw from Syria, and if he can pick a replacement to General Mattis who actually agrees with [his own] views," Jatras said. "It is imperative that he pick someone for the Pentagon — and frankly, clear out the rest of his national security team — and appoint people he can trust and whose views comport with his own."

Trump in a tweet earlier in the day commenting on his decision to withdraw US troops from Syria, said it was "time to come home and rebuild."

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On Thursday, Mattis stepped down citing the fact his views no longer aligned with Trump’s a day after the White House announced that US troops were leaving Syria.

Earlier on Thursday, the Wall Street Journal reported that Trump has ordered the US military to withdraw some 7,000 troops from Afghanistan in the coming weeks.

The president made promises during his campaign to stop expending money and lives on foreign wars to rebuild the United States.