Quite a few libertarians voted for Obama because he campaigned as a liberal on foreign policy and a moderate on economic policy, and they preferred that combination to what they deemed McCain's conservative foreign and marginally more conservative economic policy. For libertarians who lean "left" on foreign policy, Obama's rhetoric gave them hope that as president he would fundamentally reassess American foreign policy in the direction of nonintervention, and reverse various national security policies that they felt threatened individual liberty.
As Karl Rove points out, however, Obama has thus far turned out to be very liberal (statist would be a better adjective--bailouts of large corporations, political interference with bankruptcy law on behalf of special interests, going back on pledges to rein in earmarks, and so forth, can hardly be deemed "liberal" either philosophically or in their redistributive consequences) on economic policy, and not much different than the Republicans on a variety of national security and foreign policy issues. In other words, libertarian Obama supporters got the opposite of what they hoped for: a moderate on foreign and national security policy, and someone fundamentally reassessing American economic policy in the direction of bigger government.
I wonder how many libertarian fans Obama has left?
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