Halting Iran's progress toward a bomb will require the United States to make credible promises and credible threats simultaneously -- an exceedingly difficult trick to pull off. For coercive diplomacy to work, Washington may need to put more of its cards on the table.

Now, more than ever, the United States might be tempted to pull back from the world. That would be a mistake, since an engaged grand strategy has served the country exceptionally well for the past six decades -- helping prevent the outbreak of conflict in the world’s most important regions, keeping the global economy humming, and facilitating international cooperation.

Republicans need to start taking foreign policy more seriously, thinking hard about the thorny task of managing a superpower and not leaving it as a plaything for right-wing interest groups. Failure to do so quickly could be catastrophic, ceding this ground to Democrats for the a generation at least.

The amount of resources the American public and private sectors commit to all forms of welfare is massive -- the fifth highest outlay in the world. Yet the American way of distributing that money does less to reduce poverty and inequality than that of virtually any other rich democracy. The United States can, and should, reform its welfare state, and it does not need to resort to European style socialism to do so.