Senate Majority Leader Harry Reid, D-Nev., has announced he will begin the new Congress today by violating Senate rules and forcing through a set of procedural changes that will undermine Senate conservatives' ability to influence legislation. But the "Reid Plan" will have its most dramatic impact on presidential nominations, especially for the Supreme Court.

The Senate is a unique legislative body that protects the rights of individual senators both to debate and to amend. These rights are valued so highly that it takes a supermajority -- today, 60 votes -- to deny fellow senators those rights. This higher vote threshold and the prospect of extended debate encourage deliberation, compromise and moderation.

Many Senate liberals want to gut this long-standing protection for minorities. Buried in the Reid Plan is a new rule, the "standing filibuster requirement," that will allow a partisan majority to shut off deliberation and pass legislation by a bare majority. Disguised as a debate-promoting measure, this new plan is actually just a mechanism to eliminate the higher vote threshold that has long been required to proceed to final passage of bills and nominations.

This spells the effective end to minority rights in the Senate. Today's 60-vote bar to end debate will be gone, and the Senate will be transformed into President Obama's rubber stamp.

Making matters worse, Reid plans to impose his plan by breaking Senate rules with the "nuclear option," a parliamentary trick that will explode any lingering comity among senators. Once the nuclear option is deployed to impose the Reid Plan, it is far more likely to be used again and again to undermine minority rights. This pattern will ultimately make the Senate a mirror image of the House.

The most dramatic impact of the Reid Plan will be with regard to the Supreme Court, where the House of Representatives plays no constitutional role. President Obama will likely fill between one and three Supreme Court vacancies in the next four years, and he will be under enormous pressure from his base to nominate doctrinaire liberals who will reverse the decision upholding the partial-birth abortion ban, weaken personal liberties protected in the Bill of Rights, and eliminate the modest limitations on congressional power that the Rehnquist and Roberts courts have restored.

Senate conservatives will strongly oppose such a nominee. Conservatives already used their rights to extend debate to effectively block lower-court nominees such as "living Constitution" advocate Goodwin Liu and the highly controversial Caitlin Halligan. Each will be on the president's shortlist for the Supreme Court. Yet if the Reid Plan is in effect, senators will be powerless to prevent the appointment of Liu, Halligan or similar judicial activists, because the 60-vote threshold will be gone and Obama's party will just fall in line behind his choice.

The future of the Supreme Court isn't the only thing at stake. While it's unlikely that liberals will gain control of the House any time soon, it is not out of the question that Obama could command a unified, one-party government in his last two years. Under Reid's new rules, the president could pass any legislation he wanted without negotiating with conservatives and taking their views into account. That means higher taxes, more spending, bigger government and no chance of entitlement reform.

Senate Minority Leader Mitch McConnell, R-Ky., has promised massive resistance to the Reid gambit, but he will need public support. Americans should be asking themselves if they want to make it easier for Congress to rubber-stamp the president's whims, or if deliberative democracy and minority rights still matter.

Steven J. Duffield is vice president for policy at Crossroads GPS.