But what I most took away from Manza was the observation that the crisis of liberalism in America may have most to do with the lack of a vibrant, vocal left flank — thus rendering liberalism as the “vital center” of American politics, as Arthur Schlesinger Jr. once put it. Historically, Manza writes:
In the moments of grand reform, such as the 1930s/40s and again in the 1960s, liberalism could plausibly stand between the forces of conservative traditionalism and the demands of social movements from below (or resurgent left-wing thought from the intelligentsia). In the New Deal era from the 1930s to the late 1940s, the presence of strong unions, a visible Communist and other left organizational presence, and open public debate over the relative virtues of left-wing ideas in the face of a sea of trouble, gave liberalism a powerful source of centrist purpose. Similarly, in the 1960s, the civil rights movement brought pressure from below that emboldened liberals positioned in the center. To be sure, the growing tensions between older liberals and an increasingly militant student left in the late 1960s would eventually tear the Democratic Party apart, but not before some of the most sweeping and important expansions of the public sector took place, spearheaded by liberals.
But now? We can see Manza’s point in the way the Tea Party has exerted profound gravitational force not only on the Republican Party but, arguably, on the President and the Democratic mainstream — as the Tea Party can be given the credit for the fact that we’re debating the federal deficit and spending cuts at all in this moment, rather than spending more money to create jobs and stimulate the economy.
http://movementvision.org/rants-polemics/moving-the-political-center/The Tea Party may be a band of racist crackpots, but their anger and looniness pushes politicians towards the ideological change they desire. The Left has no equivalent. When members of our party cave, we shrug and say it was "the best we could do" instead of voting them out and getting equally angry..