The blunt answer is for lying about receiving blowjobs from a consenting adult not his wife...
He was caught committing several felonies. Clinton flat-out perjured himself, repeatedly, each offense a separate felony, which no one disputed.
In addition to his perjury, Clinton was guilty of obstruction of justice. He arranged for Lewinsky to give a false affidavit to the Jones lawyers denying the relationship in order to avoid being deposed. Clinton sent Betty Currie to pick up from Lewinsky the gifts he had given her, in order to keep this evidence safe from a subpoena.
As a result, Though he was not removed as his crimes did not rise to the level of removal, he was disbarred by his home state and stripped by the Supreme Court of his privilege of ever arguing a case before them.
That is why I find it so hypocritical when I hear someone like Ken Starr (who prosecuted President Clinton) defending Trump*. Lying about blowjobs is not the same as jeopardizing our national security to rig a presidential election.
Ken Starr did not Write the Special Counsel Statute that REQUIRED him to report to Congress the crimes Clinton had committed. Ken Starr also did not sign into law the extension of the Special Counsel Statute, Bill Clinton did.
... That is also why I find it extremely hypocritical when I hear Trump* supporters talking about "payback" for impeaching Trump*. ..
This is not the consensus position of nationally elected Republicans, if you claim it is you are fabricating.
... The Trump* impeachment is about exactly what the House impeached him for: Abuse of power and Obstruction of Congress...
Obstruction of JUSTICE is a crime, The Crazed House tried to make up a crime and failed miserable.
If Clinton cold not be removed after going on a felony spree, clearly Trump was not going to be removed with no crimes at all.
I was initially surprised that Democrats even attempted this, but then I remembered that they completely lost their minds on election night 2016