@magnet, there is a meaningful difference between Clinton’s obstruction and Trump’s obstruction: Clinton’s wrongdoing occurred in a private lawsuit and did not involve his actions as President or any use of his Presidential powers, while Trump’s obstruction involved Trump directly using (and abusing) his Presidential powers to shield himself from investigations.
Federalist Paper #65 lays this out clearly:
“A well-constituted court for the trial of impeachments is an object not more to be desired than difficult to be obtained in a government wholly elective. The subjects of its jurisdiction are those offenses which proceed from the misconduct of public men, or, in other words, from the abuse or violation of some public trust.” (emphasis added)
Likewise, High Crimes and Misdemeanors is a well known legal term with centuries of history. Per Wikipedia:
"A high crime is one that can be done only by someone in a unique position of authority, which is political in character, who does things to circumvent justice. The phrase “high crimes and misdemeanors,” used together, was a common phrase when the U.S. Constitution was written and did not require any stringent or difficult criteria for determining guilt but meant the opposite. The phrase was historically used to cover a very broad range of crimes.
Since 1386, the English parliament had used the term “high crimes and misdemeanors” to describe one of the grounds to impeach officials of the crown. Officials accused of “high crimes and misdemeanors” were accused of offenses as varied as misappropriating government funds, appointing unfit subordinates, not prosecuting cases, not spending money allocated by Parliament, promoting themselves ahead of more deserving candidates, threatening a grand jury, disobeying an order from Parliament, arresting a man to keep him from running for Parliament, losing a ship by neglecting to moor it, helping “suppress petitions to the King to call a Parliament,” granting warrants without cause, and bribery."
There’s a real difference here. Specifically, Trump has abused his powers and his office, for his personal gain and to harm his personal/political enemies. That’s exactly the kind of thing the impeachment clause was enacted for. Clinton on the other hand, lied in a deposition in a private lawsuit, received a $70,000 civil fine by the Judge and lost his license to practice law. There was no evidence that Clinton abused the power of his office or used the office in a corrupt fashion, and that’s a meaningful difference.
In other words, this whole issue is not about violation of the law; it’s about violation of the duties of public office, abuse of power, corruption in public office, etc. And Trump is the poster boy.