A personality disorders expert warns that President Donald Trump's mental stability could have dire consequences for both the United States and the entire world.

In an editorial co-written with former Bush White House ethics attorney Richard Painter, clinical psychologist Leanne Watt draws on her experience in treating adults with personality disorders to map out what could happen if Trump's mental health continues to deteriorate.

The two begin by arguing that clinical psychologists don't need to personally examine Trump in order to raise alarms about his mental health if they see overt signs that he has an untreated mental illness.

"Recognizing unfitness in a president does not necessarily mean waiting for a physical sign or even a catastrophic event," they explained. "Personality disorders present predictable patterns that are well documented in the medical literature. In fact, we can often find the most accurate and honest account of a public figure’s Cluster B symptoms through public records."

They then go on to warn that waiting for Trump to do something truly dangerous before speaking out about his mental health is irresponsible, especially if there are already glaring signs that his behavior could lead to catastrophe.

"At this juncture, waiting for unfitness to manifest beyond the types of observable and highly predictive behavior patterns studied by psychiatrists and psychologists is, we believe, naïve," they write. "Though remote, we cannot rule out the possibility that a president in a downward mental health spiral could destroy important global partnerships, alter centuries-old alliances and leave the United States vulnerable to terror attacks or war."

Read the whole editorial here.