Some Democrats have questioned Trump’s fitness for office, and issued calls to invoke the 25th Amendment.

Even as Trump celebrates what his supporters describe as a geopolitical victory, the president is increasingly worried that the year could end with a serious political reckoning at home.

Donald Trump, who has been impeached twice, warned of a third impeachment if Republicans lose the House in the midterms. An impeachment is a formal charge requiring a House majority vote to pass, but ...