On September 24, 2019, Nancy Pelosi, the Speaker of the US House of Representatives (House), launched a formal impeachment inquiry into President Donald Trump. The investigation was triggered by allegations that Mr. Trump had asked Ukrainian President Volodymyr Zelensky to look into the business ties of 2020 Democratic presidential candidate Joe Biden's son, Hunter. Allegedly, in order to persuade Zelensky to agree, the US president withheld federal military aid from Ukraine. So how will the impeachment process work, and what are its potential long-term implications for the president? Read on . . .