In a democracy, there’s no such thing as an election without consequences. We are not satisfied with today’s Democratic Party; we wish it was more populist and more progressive. But it is absurd to argue that little will change if Republicans take the Senate. A lot will change—and it will be for the worse. A Republican Senate, working with a Republican House, will be a wrecking crew.

GOP control of the House and Senate could be catastrophic for the environment, for workers, for women and for minorities.

Mitch McConnell, the Senate minority leader, has already promised the Koch brothers that “we’re not going to be debating all these gosh-darn proposals…like raising the minimum wage…extending unemployment…the student loan package.” And it won’t just be progressive proposals that are stymied. Consider the judges who will never make it to the bench, including the highest, if Chuck Grassley, not Pat Leahy, is in charge of the Judiciary Committee. Consider the destabilizing political circus Republicans will create if Darrell Issa’s hyperpartisan investigations into fake scandals spread from the House to the Senate.

GOP control of key Senate committees will reorder the debate. What happens, for example, if Senator Pat Toomey, former president of the right-wing Club for Growth, takes over Sherrod Brown’s subcommittee overseeing financial institutions and consumer protection? What happens to nuclear negotiations with Iran if McConnell, Lindsey Graham and John McCain are deciding when to bring up a sanctions bill?

But a GOP takeover is not a threat just because of what Republicans will do. Progressives should also worry about the many areas of potential agreement between Obama and a GOP-controlled Senate. It is Harry Reid, for example, not Republicans, who is denying the president fast-track authority on corporate trade deals. Without Reid in the way, pacts like the Trans-Pacific Partnership—which labor leaders describe as “NAFTA on steroids”—are likely to become the law of the land. Likewise, Obama and Republicans could agree to pursue lower corporate tax rates—as opposed to infrastructure investments and job creation—as their primary economic-development initiative. And let’s not forget that Obama has repeatedly floated Social Security cuts as a bargaining chip in negotiations with GOP leaders.

Perhaps the most worrying consequence of a GOP-controlled Senate will be the extension of the damaging austerity agenda. Think, for example, about the next debt-ceiling fight. Republicans have repeatedly used the debt ceiling to hold the economy hostage, but they have relented each time because they knew that they would be blamed for the consequences—not the president. But if Republicans take control of the Senate, that calculus will change. What happens when they send Obama a bill to prevent default on our debt at the eleventh hour, attached to a bill that ravages Social Security? The Republicans will be able to force the president to choose between impossible options.

They will also be able to advance the Keystone XL pipeline, ban abortions after twenty weeks, decimate an already-weak Dodd-Frank Act and shred the torn social safety net.

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