At first glance it would seem that the retirement announcements by Republican Sens. Bob Corker and Jeff Flake are bad news for the GOP. Both are highly-respected members of their caucus and one is the chairman of one of the premier committees of the chamber. But, on closer examination, the real bad news is the damage likely to be visited on the Senate as an institution.

The Senate is a very small club of 100. The addition or subtraction of only a handful of members can have a profound effect on its mood and conduct. The removal or replacement of a like number from the much larger House would not have nearly the same effect, except perhaps in the case of the replacement or defeat of a speaker or party leader.

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It is the manner of the Corker and Flake decisions that is particularly unsettling. They are being driven from the Senate not solely by the prospect of defeat at the polls but by the likelihood that even if they were to win re-election, it would be to a party struggling with how to reconcile its support for Trump’s agenda with its disapproval — always tacit — of his conduct.

The departure of Tennessee's Corker and Arizona's Flake affects Democrats as well as Republicans. Both men were known as cooperative colleagues, not because they voted with the Democrats but rather because their disagreements were never harsh. The relationship between Corker and the senior Democrat on the Senate Committee on Foreign Relations, Ben Cardin of Maryland, was the very model of how committees can be managed on a bipartisan basis even in a polarized Senate.

A well-ordered Senate requires a critical mass of dedicated institutionalists who care about the body and it can only tolerate a small number of dogmatic individuals who prefer disruption over honest disagreement. Six decades ago, a single senator, Joseph R. McCarthy poisoned the atmosphere with his reckless quest for communists in government. More recently, Sen.Ted Cruz of Texas single-handedly precipitated a federal government shutdown. And if the subtraction of a handful of good senators harms the institution, the addition of even small numbers of bad senators can undermine it.

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No savvy gambler would bet against the election of Judge Roy Moore in the Alabama special election in December. His conduct as Chief Justice of the Alabama Supreme Court marked him as a fanatical enemy of the rule of law. He may be so eccentric that his influence is limited, but the upcoming congressional elections may bolster the ranks of the crackpots in the Senate from other states. And it won’t take many of them to undermine even the routine non-controversial business the Senate manages to do.

Like any other Americans, senators dread showing up each day at a nasty and contentious workplace. Because of the Senate’s compactness, there is no place to hide. You encounter your colleagues during votes, in committee hearings and in casual contacts around the Capitol.

Meeting up with a cooperative and sensible colleague in an informal setting enables a senator to exchange information and even make deals. Those useful exchanges become less likely if cross-party contacts come under attack from extremist colleagues for whom even the most casual signs of cooperation are depicted as acts of betrayal. Even so durable an institution as the U.S. Senate can not weather that.

Ross K. Baker is a distinguished professor of political science at Rutgers University and a member of USA TODAY's Board of Contributors. Follow him on Twitter: @Rosbake1

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