Ira Shapiro and Richard A. Arenberg

Opinion contributors

As Election Day nears, America’s political debate is spiraling downward into increasingly tribal politics, fueled by excessive rhetoric spread through cable news and social media. While President Donald Trump has undoubtedly intensified the harshness of the debate by rubbing raw virtually every division in our country, the crisis in American democracy started long before Trump became president, or even a candidate.

The Senate, once a crown jewel in our political system, is failing America. At its best, which many Americans still remember, the Senate was the place where the parties came together, through extended debate and super-majority requirements, to find common ground to move our contentious, diverse nation ahead. It was the Senate that broke the Southern filibuster to enact the landmark Civil Rights Act of 1964; fiercely debated and ultimately brought about the end of the Vietnam War; held President Richard Nixon accountable for the abuses of power known as Watergate; and played a central role in every major piece of legislation to improve life in America, including Social Security and Medicare.

Former Senator and Vice President Walter Mondale aptly described it as “the nation’s mediator.” To former Senate Majority Leader Howard Baker, it was America’s “board of directors.”

We need the Senate to check and balance

That Senate has been absent for many years. In the 1980s and 1990s centrifugal forces in our politics began to erode the spirit of compromise at the heart of the Senate. The long, gradual decline of that body has turned into a deep dive into hyper-partisanship and mistrust. In the past two years, the nation most needed the Senate to be the check and balance on a chaotic administration led by an erratic, overreaching, potentially dangerous president. Instead, the Senate has given us scorched earth, partisan battles over immigration, health care, taxes and the Supreme Court, inflaming our divisions rather than seeking to overcome them.

We have worked in the Senate and studied it most of our lives. We are under no illusionsthat we can return to the political environment of an earlier era when the Democrats and Republicans were each more diverse and were less divided ideologically. There was no 24/7 media, or social media amplifying partisan conflict. The world in which that Senate existed cannot be fully replicated.

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Because we are Democrats, it may seem like an echo of that same partisan warfare, but we urge voters to demand those checks and balances. President George Washington, in his timeless September 1796 farewell address to the nation, warned, "The alternate domination of one faction over another, sharpened by the spirit of revenge, natural to party dissension, which in different ages and countries has perpetrated the most horrid enormities, is itself a frightful despotism." He emphasized, "The necessity of reciprocal checks in the exercise of political power, by dividing and distributing it into different depositaries, and constituting each the guardian of the public weal against invasions by the others..."

We believe that our present politics would be less acrimonious and more constructive if the party out of power, the Democrats, had the majority in the Senate, forcing President Donald Trump and the congressional Republicans to reach compromises. Rather than ramming through legislation and nominations on a purely partisan basis, with abuses of customs and norms which have made our democracy work, both parties would have greater incentive to come to the negotiating table.

A Democratic Senate is best step forward

Historically, previous presidents — both Republican and Democratic — claimed important legislative triumphs when working with a Congress — and particularly the Senate — of the opposite party. Richard Nixon and a Democratic Congress created the Environmental Protection Agency (EPA) and strengthened the Clean Air Act. George H.W. Bush and a Democratic Congress worked out the Americans for Disabilities Act. Bill Clinton signed welfare reform and a balanced budget legislation working with a Republican Congress.

Those experiences demonstrated, the wisdom of Mitch McConnell’s observation that only the Senate could produce legislation which commanded broad national support because the legislation resulted from the parties working together. “People are not elected to the Senate to get everything they want,” McConnell wrote in his 2016 memoir, "The Long Game," “this is not an all- or -nothing place.” With a Republican president and a Republican Congress, McConnell has obviously changed his view, but he had it right the first time.

Control of the Senate will turn on the outcome of six to eight races which are currently too close to call. The last thing our divided country needs is more fiercely partisan Republican warriors like Kevin Cramer in North Dakota, Marsha Blackburn in Tennessee, Josh Hawley in Missouri, Martha McSally in Arizona, or Rick Scott in Florida to come to the Senate to join in the Republican leadership's unthinking support of the Trump effort to use a narrow majority to enact his extreme agenda by whatever means possible.

We recognize that our argument will not convince the many Americans who believe that these elections are only about supporting or opposing President Donald Trump. But for those voters who are deeply concerned about the level of partisan warfare and the increasingly dangerous rhetoric, whether Democrats, Independents or concerned Republicans, a vote for a Democratic Senate candidate is the most promising step forward for America.

Ira Shapiro, a former Senate staffer and Clinton administration trade official, is the author of "Broken: Can the Senate Save Itself and the Country?" Richard A. Arenberg, a visiting professor at Brown University and a former aide to three senators, is the author of "Congressional Procedure: A Practical Guide to the Legislative Process in the U.S. Congress." Follow them on Twitter: @ShapiroGlobal and @richarenberg