Former Pentagon chief, Jim Mattis rebuked his former boss, President Donald Trump on Wednesday, accusing him  of trying to “divide” America and failing to provide “mature leadership”.

His rebuke comes as the United States is rocked by protests over the death of an unarmed black man, George Floyd, by a policeman.

Mattis resigned in December 2018 over Trump’s ordering of a full troops withdrawal from Syria.

“Donald Trump is the first president in my lifetime who does not try to unite the American people — does not even pretend to try,” Mattis wrote in a statement posted online by The Atlantic.

“Instead, he tries to divide us. We are witnessing the consequences of three years without mature leadership,” he stated.

Mattis said he was angry after witnessing events of the last week which saw Trump threaten a military crackdown on American citizens as nationwide protests turned violent in some cities. The demonstrations have mostly been peaceful, but some have degenerated into violence and looting as night falls.

Mattis also slammed the decision to use force to clear peaceful protesters from near the White House on Monday to allow Trump to pose for photographs at a nearby church which was attacked by protesters, calling it an ‘abuse of executive authority.’

“When I joined the military, some 50 years ago, I swore an oath to support and defend the Constitution,” Mattis asserted.

And he continued : “Never did I dream that troops taking that same oath would be ordered under any circumstance to violate the constitutional rights of their fellow citizens — much less to provide a bizarre photo-op for the elected commander-in-chief, with military leadership standing alongside.”

On his part, Trump dismissed Mattis with a tweet:

“Probably the only thing Barack Obama and I have in common is that we both had the honor of firing Jim Mattis, the world’s most overrated General.”

Mattis was head of US Central Command when Obama fired him in 2013 over his hawkish views on Iran.

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