The editors of National Review have assembled a collection of talented writers to make, once again, the case for important truths—namely, against Socialism, now resurgent and trendy, and for free markets, now embattled.Socialism is back. T. S. Eliot said that “there is no such thing as a Lost Cause because there is no such thing as a Gained Cause.” We thought our Gained Cause was having vanquished domestic socialism forevermore after the collapse of Soviet Communism in 1989. In the 1990s, Bill Clinton operated within the broad economic consensus established by Ronald Reagan, and when Republicans called Barack Obama a socialist, some on the left considered it a racially charged smear. But here we are: A self-avowed socialist nearly won the Democratic nomination in 2016 and is a serious contender this time. Another socialist, Alexandria Ocasio-Cortez, is the hottest thing in progressive politics today. The Green New Deal and Medicare for All are proposals for sweeping aggrandizements of government power on a scale not seen in this country since the New Deal, if ever. Meanwhile, some on the right are raising questions about free markets, or even rejecting them. If National Review exists for nothing else, it is to stand up for important truths, even when they are out of favor. It is in that spirit that we publish this book, an anthology of articles and essays from our twin special issues: “In Defense of Markets” and “Against Socialism.” If our cause wasn’t nearly as gained as we thought two decades ago, it is incumbent on us to make the argument for it more vigorously than ever.