In a paper presented last year to the Midwest Political Science Association, professors Matt Grossmann (Michigan State University) and David Hopkins (Boston University) empirically demonstrated what most people in Washington already know. To wit, the Republican Party is primarily a vessel for an ideological movement while the Democratic party is a less ideological coalition of left-leaning politicians and interest groups seeking government favor.

What makes the Grossmann and Hopkins paper interesting, however, is their analysis of how each party’s political culture influences how they go about the business of governing.

The Democrats operate in a fashion consistent with the popular understanding of politics. Grossmann and Hopkins argue that:

Because [Democrats] are primarily motivated to engage in party politics in order to make concrete programmatic demands on behalf of their members, left-leaning officeholders, activists, and voters are more likely than conservatives to take a close interest in the substantive details of the legislative process and are more willing than their counterparts on the right to compromise in order to win partial achievement of their policy goals if the alternative is simply inaction.

Within the GOP, however, the constant tension between doctrinal purity (enforced by an influential cadre of movement leaders devoted to publicly policing ideological orthodoxy) and the need to compromise in order to pass legislation makes it difficult to move an ambitious conservative agenda through Congress. There are never enough purists to overcome Senate filibusters or override presidential vetoes. Republicans who respond by looking for compromise to marginally improve existing laws are savaged by ideological policemen for compromising on principle. Paralyzed by their inability to pass meaningful legislation, Republicans spend most of their time on “messaging” bills and resolutions that have zero chance of enactment.

Defensive operations, however, are made easier by the party’s adherence to doctrine. Ideological policemen keep potential defectors in line. Compromises aren’t necessary to hold the legislative chokepoints that allow small groups of ideologically united minorities to hold off legislative majorities.   This likely helps to explain why the Left has had a more difficult time over the past several decades passing legislation to expand state power.

Republican political behavior makes sense given the political landscape. The electorate responds to conservative rhetoric about limited government in general but not to conservative policy in particular. Moreover, most Republican congressmen are more at risk from an ideologically motivated primary challenge than from a Democrat in the general election. Commitment to ideological principle at the expense of legislative accomplishment is the safest strategy for Republican officeholders.

Republican political behavior, however, does not make sense given their stated objective; rolling back the size and scope of government. That requires legislation. Legislation requires politics. Politics requires compromise. And compromise requires the party to abandon rigid commitment to principle.

Fortunately for Republican officeholders, their ideological base does not punish them for failing to deliver the goods. Ted Cruz will never provoke a Tea Party challenge for failing to roll back government. He will provoke a challenge, however, if he fails to demand unachievable political outcomes.

Rhetorical commitments aside, the GOP is functionally the party of the status quo. Their strategies and tactics optimize defensive operations but they make it nearly impossible to undertake offensive operations. If slowing the pace by which government grows is the objective, then Republican modus operandi makes sense. If reversing the tide of government is the objective then Republicans are their own worst enemies.