Constitutional principles apply to both Democrats and Republicans.
LET'S SAY THE congressional committee's investigation is about the terrorist attack on the U.S. compound in Benghazi.
And let's say then-Secretary of State Hillary Clinton turned over some material to the committee and kept other things secret.
Then let's say the committee subpoenaed Clinton to appear for testimony and questioning and she was a no-show.
Finally, let's say President Barack Obama dismisses the whole thing as a "witch hunt" and asserts executive privilege to block access to evidence while telling everyone in his administration, past and present, they must defy subpoenas, refuse to testify or turn over any sought-after materials.
WOULD THE REPUBLICAN majority in Congress at the time have looked upon that as a constitutional collision?
The ugly truth is that today's politicians are incapable of acting on principle, even when that principle involves upholding the most cherished document in America, the United States Constitution.
Instead, all that matters is whether the administration being investigated has an "R" or a "D" attached to it.
There were plenty of serious issues deserving the deepest dive in the Benghazi attack. Republicans were right to press hard to get to the bottom of it. Democrats were wrong to circle the wagons and politicize the issue.
Likewise, there are clear justifications for post-Mueller hearings on Russia's election tampering and subsequent attempts to impede the federal investigation. The strategy that is emerging, with the Article II branch of government digging in to block Article I proceedings is an assault on constitutional separation of powers.
HERE'S WHERE THE argument usually turns toward "what-about-isms." As in, "What about Hillary Clinton's lies and obstructions and email servers" or whatever.
No objections. Republicans were right to push through all that, drive hard for the facts, and they did.
But whatever foot-dragging Clinton or Obama may have tried (and failed, by the way) does not justify barriers today. "What-about-isms" are just plain dumb. It's like trying to tell a cop he can't write you a speeding ticket because somebody passed you a mile back.
Congress has the constitutional authority and obligation to investigate and exercise oversight. That was true of the Benghazi probe. It was true of the Iran-Contra probe, and the Watergatge probe before that. And it's true today with Trump. Politicians do not take an oath to defend their party. They take an oath to defend the Constitution.