The World Mental Health Coalition made the statement a month after warning Congress that the stress of impeachment could cause Mr Trump's mental state to deteriorate to a dangerous level.
"We have been seriously warning about this for some time. The US Congress must act immediately and forcefully without further delay," the group said in a statement obtained by The Independent shortly after the president struggled to pronounce words and sniffed repeatedly while delivering a scripted statement on the Iran crisis at the White House.
Mr Trump, they said, is "psychologically and mentally both dangerous and incapacitated" and has a presentation that is "consistent with a person who, when his falsely inflated self-image is questioned, or when his emotional need for adulation is thwarted, lashes out in an attempt to restore his sense of potency and command over others".
The group noted that while senior military leaders must pass yearly psychological evaluations, their commander-in-chief is exempt from such a requirement despite being "the person in most need and who is a maximum danger", and added that current tensions in the Middle East make this a "critical time", at which Americans "cannot wait any longer to deal with the dangerous situation caused by a mentally compromised person acting in erratic, reckless, impulsive, and destructive ways".
Because Congress has the constitutional power to declare and finance wars, it must "act immediately to take any war-making powers out of his hands", they said, adding that it is "imperative that the Congress be equipped with accurate information" from those in the medical community who are qualified in "assessment and management of psychological dangers".
"We urge Congress to consult with us for a profile, if not evaluation, and to take seriously the mental health aspects that are at play in this mentally impaired president," they said.
While no one in the group has examined the president personally, one member, George Washington University Professor Dr Richard Zinner, told The Independent last month that the so-called "Goldwater Rule" which purportedly prohibits psychiatrists from diagnosing a person they have not examined is "more of a principle or a standard", which is different from a rule "because the preamble of the code of ethics of the American Psychiatric Association that establishes the basic guidelines for the ethical canons says that a psychiatrist's responsibility, first and foremost, is to his or her patients and to society and to his colleagues and himself in that order".
The group's president, Yale University professor Dr Bandy Lee, told The Independent that Mr Trump's decision to respond to an incursion into the US embassy in Baghdad with an airstrike against Iranian General Qassem Soleimani was expected because he opted for the most extreme of the options with which he was presented.
Dr Lee noted that more than 800 of her colleagues had signed a petition warning Congress that the stress caused by the impeachment proceedings against him "would most certainly send him into a seething rage" because Mr Trump's "fragile, falsely inflated self-image could scarcely withstand such a wound". She added that from her perspective as a physician and mental health professional, it would be “inconceivable” for someone who meets full criteria for an involuntary mental health evaluation since long ago, based on dangerousness to others and the self” to be able to retain “full command over warmaking powers and nuclear weapons”.
"The fact that the Pentagon officials were stunned, and even considered presenting him with the assassination option, starkly reveals how little those around him understand him and how ill-equipped they are to manage him," she said. "They essentially handed him the craved match to throw into a field of gasoline".
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