In a controversial move, the Republican-majority U.S. Senate has begun impeachment proceedings against President Donald J. Trump on Tuesday, exactly three years after his inauguration.

After receiving from Congress the articles of impeachment on charges of abuse of power and obstruction of Congress, Senator Mitch McConnell, the Republican majority leader in the Senate, has made public the rules of the controversial process, not without pressure from some of his colleagues.

While McConnell had praised Republican cohesion against the process, the risk of losing his majority has been stronger than his determination to exonerate the president as soon as possible.

Within two business days, beginning at 1 p.m., Democratic managers handpicked by House Speaker Nancy Pelosi will have to make their case for why they believe Trump should step down as U.S. president.

However, considering the deep bipartisan divide on Capitol Hill, most of Tuesday's day was devoted to a tug-of-war to determine just the rules of the game, between Republican intransigence in accepting possible testimony and evidence, and Democratic determination to pass amendments.

Democratic minority leader Chuck Schumer tried to get the Republicans to authorize subpoenas for White House, State Department and Office of Management and Budget documents, as well as a request that Mick Mulvaney, acting White House chief of staff, testify before Congress.

In the view of New York Times editor Carl Hulse, the Democrats' insistence on trying to make their Republican counterparts give in is an attempt to “show their supporters that they are going to put up a fight, and to force Republicans into votes that show how far the party will go to shield Mr. Trump from scrutiny.”

As the hours passed, tempers grew hotter as diplomacy and professionalism went down the drain.

The clashes between House managers and the president's lawyers reached such a point that even Judge John Roberts had to admonish both sides.

Finally, late at night, the Senate finally adopted the ground rules for the impeachment trial, postponing the decision on whether to bring witnesses to the floor until long after the process had begun, according to the Washington Post.

"The GOP concerns over the rules underscored the narrowness of the majority that McConnell will have to tend to as Trump’s impeachment trial proceeds,” the newspaper said, "while also balancing the demands of a White House that has repeatedly pushed for a swift acquittal of the president.”

Over the next two days, the scenario is likely to be one of the repeated clashes between the two sides, with the expectation that some surprise will change the course of a story that we anticipate will result in the president's acquittal.