Taxes pay for our civilization.

Better it be spent on healthcare, education, infrastructure (all services that will not only improve the lives of the average American but also create plenty of decent paying jobs for Americans in the process) than on pointless wars. The better off the average American is, the more comfortable they will feel about taking business risks/consuming more which in turn benefits the economy. Not to mention the rich tends to hoard money, money that otherwise would be pumping into the economy. The nation can't thrive without a dose of socialism.