Labor activist Thomas Geoghegan recently had a piece in the New York Times that rightly decries how current filibuster practices are imposing supermajority requirements on non-treaty legislation like health care reform.
Ironically, treaties have now been effectively stripped of their supermajority requirements. The Constitution empowers Congress to regulate foreign commerce, and requires that treaties be approved by a Senate supermajority. According to the Federalist Paper 75, this was to ensure popular legitimacy of international instruments that would operate as domestic laws. Yet, the controversial 2005 Central America Free Trade Agreement - which the founders would likely have considered a treaty - passed by only two House votes. The process on this and similar deals was rushed through Congress via the Fast Track mechanism (itself receiving only one vote in the House in 2001), which limits debate and gives expansive powers to the executive to design and sign trade agreements.
Public policy will continue to face a legitimacy crisis if pro-worker legislation is perpetually blocked, while anti-worker trade deals skate through Congress.