When exploring the whole Trump Ukraine saga it is important to see everything on a timeline. By doing so you can see when things happened and make more sense for why certain actions were taken. This is vital because the entire case seems to hinge around the motivations of President Trump.
2014-16 Biden Shady dealings
Early 2014 Biden is assigned as top US official over Ukraine.
April 15 2014 Biden’s son and his business partner are paid for the first time by Burisma the same day his business partner Devon Archer meets with Joe Biden in the White House.
April 22 2014- Biden goes and tells Ukraine to ramp up domestic natural gas production.
Dec 2015- The investigations into Burisma by the Ukrainians (Via Viktor Shokin) goes public in the US via a NYT article.
March 2016- Biden withholds aid until they fire the prosecutor (Viktor Shokin) investigating Burisma saying he was not doing enough to fight corruption including at places like Burisma. Shokin claims he was looking into corruption at Burisma and that is why is was removed.
Spring 2016- Oct 2019 -Investigations in Burisma did not continue under Shokins replacement (Yuriy Lutsenko). Oct 2019 - Prosecutor General Ruslan Riaboshapka announced that all 15 investigation cases against burisma will be reviewed.
2016 DNC collusion with Ukraine
March 2016 Trump becomes the frontrunner for the Republicans.
April 2016 DNC sends an operative ( Alexandra Chalupa ) to dig up dirt on Trump and his associates. (Source)
May 2016 Ukrainians coordinate with Chalupa to stop trump (Source)
Aug 2016 Paul Manafort forced to resign after Ukrainian officials release records
August 2016 The Ukrainian ambassador attacks Trump in an article.
Nov 2016 Trump wins the election.
2017- Initial Trump Suspicions. Jan 2017- Politico publishes a story about DNC coordination (via Chalupa) with Ukraine government officials against Trump.
July 2017- Trump floats the theory of Ukrainian meddling in US elections.
2018- Trump suspicions intensify.
April 2018 Trump says he wants to fire the ambassador to Ukraine (Yovanovich) because he heard she did not support his policies.
Summer 2018 A Ukrainian prosecutor Kostiantyn Kulyk, who says they have evidence of election interference and Biden corruption, comes forward and wants to go to US but are denied visa's by Yovanovich embassy staff.
Fall 2018 Giuliani goes to Ukraine to investigate 2016 election meddling.
2019- Trump begins taking actions
Spring 2019- Giuliani tells Trump Yovanovitch cannot be trusted.
March 28 2019 Ukraine reopens investigations into Burisma
March 31- Zelenski becomes president
April 2019 Joe Biden announces he is running
April 2019- The prosecutor Lutsenko tells reporter John Solomon that Yovanovitch had a shady "do not prosecute" list.
April 21 - Zelenski is made President Trump has first contact and congratulates him.
April 25- Trump calls Sean Hannity and mentions the need to investigate the DNC.
May 6- Yovanovitch is fired
May 19- Trump mentions to Steve Hilton on Fox News that Biden seems corrupt based on his firing of the prosecutor.
June 18- Aid is officially announced.
2019- The key events
July 10- Sondland and top US officials meet. Sondland leaves presuming a meeting with the president is conditioned on aid.
July 18. Aid is officially on hold
July 25. Trump has call with Zelenski
July 26. Zelenski tells our ambassadors all went well in call.
2019- The rumor mill starts turning.
Aug 9- Sondland keeps negotiating a meeting time but says Trump wants investigations in return.
Aug 12- Whistleblower complains about call with Zelenski
Aug 27- Bolton meets with Zelenski. Aid not discussed.
Aug 28- Politico announces aid being held.
Sep 1- Pence meets with Zelinski. No discussion of the Biden’s but there was discussion of corruption issues and aid hold.
2019- Congress gets involved
Sep 9- Congress is notified of whistleblowers complaint.
Sep 11- Aid is released
Sep 24- Impeachment inquiry begins
Sep 25- Transcripts released
So what happened?
Since the 2016 election President Trump has been VERY leery of the Ukrainians, since, (from his perspective) they had worked with the DNC to try and sabotage his election. After hearing from people he trusted that his ambassador to the Ukraine (Yovanovitch) was a Clinton supporter who had denied visas to informants who were offering information about the corruption between the DNC, The embassy and the Bidens, Trump lost trust in our normal Ukrainian diplomatic channels fearing they were corrupted by anti Trump insiders.
Therefore, In late 2018 Trump sent his trusted personal attorney Rudy Giuliani (who Trump believes to be an excellent corruption fighter) to look into what was going on. Rudy comes back with all sorts of information. He essentially says that Yovanovich is compromised and that he has good reason to believe that there is deep state corruption between the embassy, the DNC, the Bidens and others since we first got heavily involved in Ukraine during the 2014 Russian invasion. In the midst of all this a new President is elected in Ukraine. Trump is not sure if this President is going to be part of the corruption schemes or not. He really would like the cooperation of this President in looking into these multiple connections to 2016 corruption in his country. Some of the major leaders in Ukraine get together in a July 10th meeting and the aid is put on hold. Sonland PRESUMES it is because President Trump wants to look into the Bidens so he can use it against them in 2020, but he fails to recognize the broader context of the 2016 election interference.
Trump then has his call with Zelenski and never mentions the Bidens but talks about many other things. Then, in passing, Trump says our country "has been through a lot" (a reference to 2016) and he wants him to do us "a favor" (looking into the 2016 election meddling). In fact, Trump goes on and on in the transcript about getting Giuliani (who Trump felt had the information about the DNC corruption) to the Ukraine to help get to the bottom of the 2016 meddling issue. However, with Sondland PRESUMING things about the Presidents motives, Sondland and a few others get the rumor mill turning hard saying that this is all about 2020, when it was in reality about 2016. This gossip and presumptions among US officials is what eventually leads to the whistleblower complaint a couple weeks later (hence, all the witnesses called by the Dems and their connection to Sondland)
So... what in all this was an impeachable offense.... Nothing. It should not be surprising that Trump (in his typical brash fashion) bunched the Bidens, the DNC, The Embassy, crowd strike theories and the Ukrainian government into the same ball of corruption that he wants help looking into. Based on the context it seems these issues are not itemized in Trumps mind. This is why the answer to the question "why was the aid held" was "worry about corruption" (which is not false, though it is vague). It's also why Mick Mulvaney (who for sure knew why the aid was held) came out and flatly said the aid was held up to get cooperation with investigations into 2016 election meddling and now John Bolton (who for sure would have known as well) has essentially said the same thing. The problem now is that the President's defense team has tried to claim there was no connection to the aid hold and the investigations, but that does not match the facts. Still, in the end that does not really seem to matter, here is why...
Trump may have been wrong in his suspicions about the 2016 Ukraine connection with the Crowd strike server. He may (or may not) be wrong about Bidens corruption. He may have been given bad info from Giuliani. All this points to a bad decision perhaps, but not an impeachable case of bribery. There is absolutely nothing out of the ordinary about a nation withholding aid until they get cooperation in investigations connected with possible election meddling.
Whats crazy is that the Democrats seem to agree! That is why their case is based on two silly charges and not bribery or any actual crime. Their charges are... 1) Obstructing congress (which is essentially them whining about the nature of executive privilege and the fact they did not follow proper procedure with issuing the subpoena)- Total Nothingburger. 2) Abuse of power- which has no legal standard and is basically is just some of the Democrats claiming that Trumps withholding of aid (which we now have established was primarily about 2016 Election meddling and DNC collusion) was not legitimate. Sorry guys this just is not going to cut it. It's simple as ABC A) Withholding aid when there is reasonable grounds to suspect corruption and election meddling is perfectly legitimate.
B) Obstruction of congress is a nothing-burger (sorry you have to go to court if you want the president to comply, its called executive privilege) C) Abuse of power is not a thing if (A) above is true... which it is.
Time to end this sham.