In the wake of Scott Brown's recent victory in the Massachusetts Senate election to replace Ted Kennedy, some have asked: Why is it such a big deal that the Democrats no longer have a 60-vote majority in the U.S. Senate?

In a Senate in which the minority was willing to work with the majority to seek compromises to address the problems facing the country, it wouldn't be a big deal at all. However, given the recent behavior of the Senate Republicans, the lack of 60 votes may bring all progress to a screeching halt.

The rules of the Senate are designed to operate by consensus. Those rules are designed to provide senators in the minority with the tools to slow things down. That power was intended to be used on rare occasions when the minority intensely believes that the majority is headed down a path that poses grave danger to the country.

Used well, the tool of the filibuster can force moderation and consensus. Used destructively, as it has been recently, it can bring total gridlock, preventing even a supermajority from addressing the problems of the country.

According to a recent survey by the Pew Center for the People and the Press, only about a quarter of the public (26 percent) knows that it takes 60 votes in the Senate to break a filibuster and force a vote on a bill. Over the past three years, Republicans in the Senate have exploited that lack of awareness by the public and have used the filibuster as an obstructionist tool to gain political advantage, by depriving the majority party of the ability to govern effectively.

In the three years since the Republicans fell back into the minority in the Senate, their reckless use of filibuster threats has required Senate leaders to file 212 cloture motions (the procedural move required to end a filibuster or filibuster threat).

Some analysts have rightly pointed out that Republicans were able to pass significant legislation during the Bush administration with majorities substantially below the 60 vote filibuster-proof majority, which is true.

However, the current atmosphere in Washington is far more polarized than even a few short years ago, arguably substantially in part as a result of the Republican's overuse of the filibuster to thwart the will of the majority -- of both the public and of the Senate. By way of example, during the 110th Congress (2007-08) there were 139 cloture motions with Republicans in the role of leading filibusters. During the 108th Congress (2003-04), when Democrats were in the minority, there were only 62 cloture motions filed.

Republicans have hardly reserved their filibuster threats for issues of great national consequence, or to force compromise. Instead, they have forced votes to end filibusters on routine appointments and budget bills. They have even filibustered legislation like the Travel Promotion Act (a bill to promote leisure, business and scholarly travel to the U.S.) and the Revolutionary War and War of 1812 Battlefield Protection Act.

Those last two pieces of legislation hardly seem sufficiently controversial to warrant the use of an extraordinary tool like the filibuster.

In fact, the Travel Promotion Act ultimately passed the Senate with 79 votes and the Revolutionary War Battlefield Protection Act passed with 77 votes. Despite the fact that those measures enjoyed overwhelming majority support, Senate Republicans chose to obstruct those bills as a means to clog the legislative pipeline and prevent progress on other priority legislation important to the American people.

In many cases, Republicans have even gone so far as to filibuster the procedural motion to allow debate on non-controversial measures to begin -- a reckless use of the filibuster that almost certainly wasn't contemplated by those who drafted these rules so many years ago.

There once was a time that Republicans in the Senate played the role of a constructive minority, taking the ideas of Democrats, trimming off some of the excesses and offering ways to improve the legislation. By their recent actions, Republicans have signaled that those days are long since gone.

Yet, so far, Republicans have paid no political price for these tactics. In part, that was possible because the Democrats had 60 votes and the media focused on why the Democrats couldn't unify to pass legislation over Republican objection.

But things have changed. Once Senator-elect Brown is seated, the Republicans will have 41 votes in the Senate. With that comes the power to stop all legislation that they as a party choose to block. There is virtually no way around them if they stick together.

As President Barack Obama indicated in his State of the Union Address last week, now that the Republicans have the power to block any legislation that they choose, they now have the responsibility to govern as well.

Will they live up to that obligation? Only time will tell.

Where Democrats can work with the minority to seek compromise while preserving their core values, they should. When their efforts are met with the continued obstructionist tactics of the minority party, Democrats must be prepared to take the case to the voters to ensure that the GOP is held accountable for their willingness to play political games instead of working constructively to address overwhelming national problems.

Then, in November, the voters will get the chance to choose the way forward for the country.