Daniel Strand on the Juicy Ecumenism blog, says that, unlike Catholics, Evangelicals lack a framework for addressing political issues.
If I could state it succinctly: I get the impression they want to say a lot about politics without having to know much about politics, either intellectually or historically. To add a further complicating factor: it’s not clear how the theology that they present should be related to politics, both in term of theory and practice. For a group that usually offers profoundly biblical and well-thought positions on a host of pastoral, doctrinal, or cultural questions, their engagement with politics is woefully underdeveloped.
Taking a moral stance on an issue is one thing, having a constructive way to think about addressing these issues is another. And while pastors and theologians do not have the complexity of knowledge that policy experts have, they must engage at some level with empirical data and develop a political framework for thinking through these questions, otherwise they are in danger of falling in the trap of so many progressive Christians who combine maximal moral outrage with equally maximal political idealism that paints marvelous and beautiful worlds that are utterly impractical.
That last phrase is a pretty good explanation of shallow politics.