Congressional Republicans have laid down their marker: They are not going to argue the facts surrounding the impeachment of Donald J. Trump.

Congressional Democrats are arguing that the facts are beyond dispute. They are acknowledged as being true.

So what is left, then, for Congress to consider? I am left to conclude only that the facts as presented either are impeachable or they are not. That’s what I get from all of this.

I happen to believe that a president who invites foreign involvement in our election has committed an impeachable offense. It is an abuse of the immense power of his office. Trump allies, I am presuming, believe otherwise. If that is their belief, then why are we not hearing them argue that point?

Moreover, I also believe that obstruction of Congress also is an impeachable offense. The U.S. Constitution gives Congress all the authority it needs to conduct an investigation into executive branch behavior. When a president orders all key witnesses to ignore congressional subpoenas, I believe that constitutes an impeachable offense.

What do congressional Republicans use to justify their resistance to these two articles of impeachment that are heading inexorably to a vote in the House Judiciary Committee and then to the full House of Representatives?

I am just a voter, a patriot and someone with a deep interest in our government. I believe the president has violated his oath of office. Believe me or not, but I am waiting to hear someone on the GOP side speak to the facts at hand.

That specific defense is not forthcoming, or so it appears as we hurtle toward impeachment.

So we’re left with one side arguing that abuse of power and obstruction of Congress are impeachable offenses. The other side seems to believe they are not impeachable.

What is the rationale of those who cannot defend the indefensible?