U. S. President Donald J. Trump has got to go and his July 25 phone call with Ukrainian President Volodymyr Zelensky is Exhibit A in what should be a successful impeachment drive led by the U. S. House of Representatives.

Trump has made corruption one of America’s top exports since he took office on Jan. 20, 2017. He’s cozied up to dictators, most notably Russia’s Vladimir Putin, while damaging American credibility by undermining alliances with leaders of European and other democratic allies.

His pressure on Zelensky to investigate ex-U.S. Vice President Joseph Biden and his son, Hunter, while urging his Ukrainian counterpart to get to the bottom of fanciful theories spun by his private lawyer, Rudolph Guiliani, shows just how unhinged and disconnected the president is from reality. The Oct. 9 arrests in the U.S. of Guiliani’s clients, Soviet-born Lev Parnas and Igor Fruman, show that Giuliani’s lies to Trump are being exposed. Parnas and Fruman are accused of funneling foreign money to influence U.S. elections, which is against the law, and using two corrupt former Ukrainian prosecutors — Viktor Shokin and Yuriy Lutsenko — to smear former U. S. Ambassador to Ukraine Marie L. Yovanovitch, prompting Trump to abruptly recall her in May for alleged disloyalty.

While Guiliani’s smear campaign has poisoned Trump’s attitude towards Ukraine, the 45th president has been exposed as incompetent and unworthy, warranting his removal from office.

Key documents in the impeachment inquiry of U.S. President Donald J. Trump:

White House transcript of July 25 phone call between Trump and President Volodymyr Zelensky released on Sept. 25

Whistleblower’s complaint against Trump released on Sept. 26

Text messages released on Oct. 3 by chairmen of 3 U.S. House committees

Prepared remarks of ex-U.S. special envoy to Ukraine Kurt Volker to U.S. House committees on Oct. 3

Prepared remarks of ex-U.S. Ambassador to Ukraine Marie L. Yovanovitch to U.S. House committees on Oct. 11

Affidavit of ex-Ukrainian Prosecutor General Viktor Shokin on Sept. 4 on behalf of exiled Ukrainian oligarch Dmytro Firtash

Highlights of U.S. Vice President Joseph Biden’s 6 visits to Ukraine and key policy speeches