Allan Meltzer summarizes his case for capitalism here:
My book, Why Capitalism?[,] offers my explanation of the success of democratic capitalism and the failure of alternatives. Democratic capitalism has three unequaled strengths. It is the only system that achieves both economic growth and individual freedom, and it adapts to the many diverse cultures in the world. Adapting to cultures means that it works well with people as they are, not as someone would like to make them. Democracy works to remove the most common criticism of capitalism - that it generates inequality in income distribution. Voters choose the tax rates and income redistribution that satisfies a majority of voters, never all of them.
OK, he's written a whole book on this, and I for my part am not about to embark on a general assessment of capitalism, covering all aspects of it. To borrow from Alfred P. Doolittle in My Fair Lady, that could take up my whole day. But there are two things I would point out about this summary.
First, for all that democracy is a value not to be compromised, democratic capitalism has nowhere 'removed' either inequality in income distribution or, therefore, the criticism of it. Second, the inequalities that matter morally extend beyond the distribution of income, to the more general distribution of resources. These are resources of every kind: from productive assets, to educational opportunities, to health and food and housing. Access to and control over these things is still very unequal even in the most democratic of capitalist societies.