Bribery is the Word for This
Forget quid pro quo. It misses the point. Donald Trump was engaged in bribery, the impeachable offense detailed in Article II, Section 4 of the U.S. Constitution.
Bribery: "the act of persuading (someone) to act in one's favor, typically illegally or dishonestly, by a gift of money or other inducement"
Quid pro quo: "a favor or advantage granted or expected in return for something" literally "something for something."
Testimony in the House impeachment hearing is clear (unless you listen exclusively to the ever more shrill Sean Hannity or Rush Limbaugh). Donald Trump in his July 25th call with Zelensky wants "a favor." [Read the rough transcript.] Like any seasoned mobster, Trump hints at what he is offering in return for the "favor" he asks. Funds already approved by Congress and essential to Ukraine's ongoing effort to stop Russian aggression in its eastern provinces have been held up by Trump's order. Trump knows this. Zelensky knows this. Giuliani and Sondland know this. It doesn't need to be spelled out in a single phone call. That is not the way these things work. (Here's the timeline.) Toward the end of the call Trump offers something else Zelensky wants, an honored visit to the White House to burnish Zelensky's image back home. Trump offers this right after he re-iterates that the contact people for the deal are "Rudy and Attorney General Barr." Such offers, "I will do x and y if you do z" are never quite explicit.
The inducement in return for the political "favor" Trump wants is two-fold, final release of the funds Trump has specifically held up and a White House visit. This is bribery. Call it what it is.
We learn in other testimony something I find in some ways more damning. Trump isn't so much interested in the performance of or even the result of an investigation. He is most interested in the Ukrainian government making an announcement that it is opening an investigation. It is the public doubt engendered by the announcement of an investigation that Trump really wants--a purely personal political maneuver. An actual investigation is immaterial to his purpose.
Keep to the high ground, Jerry
P.S. Some may wonder why not "extortion"? It is a term very closely allied with bribery, but not specified in the Constitution. Trump functions as a gangster. He is making a threat to withhold vital funds unless Ukraine offers him the "favor" of announcing an investigation of Trump's political rival.
Extortion: "the practice of obtaining something, especially money, through force or threats"
The difference is linguistic, a matter of nuance. Bribery is specified in the Constitution.
P.P.S. I watched Sean Hannity on Fox "News" last Wednesday evening (almost by accident). It was instructive of desperate Republican tactics. Besides the loaded wording and belligerent Republican Congressperson interviewees, he even went to the trouble of showing a video of Adam Schiff reading a Republican screed against impeachment, a video carefully edited to make it look as though Schiff were damning himself. I've never seen purer, shriller, partisan propaganda.