What we are learning in the hearings goes beyond Mr. Trump’s misadventures in the Ukraine, where he pressured a foreign ally to dig up dirt on his political rival. It casts doubt, as well, on the nature of the US relationship with other countries, including the Philippines. So far, professional, career diplomats in the service of the US State Department have testified how Mr. Trump’s agents—including his personal lawyer—conspired to pressure the newly elected Ukrainian government to dig up dirt on his political rival, Vice President Joe Biden. The lever that Mr. Trump used was the withholding of US military assistance to the Ukrainians, who needed it to fight off a Russian invasion. Mr. Trump’s efforts also included besmirching the reputation of a career US ambassador, whose service to her country has spanned over three decades, simply because Mr. Trump and his cohorts felt she stood in the way of their Ukranian machinations. The basis of Mr. Trump’s pressure campaign in the Ukraine was a now-discredited conspiracy theory that it was the Ukranians, not the Russians, who meddled in the 2016 US election. Mr. Trump, who lost the popular vote but won the count in the US Electoral College, continues to bristle at the widely held view that his election victory was helped by Russians who mounted a massive online disinformation campaign on social media to destroy his rival Hilary Clinton, as well as Russian government hackers who electronically stole documents and emails from Clinton’s presidential campaign and the Democratic National Committee.