... allowances less undistributed offsetting receipts. Economics and National Security: Issues and Implications for U. S. Policy Congressional Research Service 13 of a burden is this on the U. S. economy? ... For an analysis of business taxes, see CRS Report R41117, Business Tax Issues in 2010, by Donald J. Marples and Mark P. Keightley. Economics and National Security: Issues and Implications for ... Iran), or for its participation in alleviating the effects of natural disasters (such as earthquakes, tsunamis, infectious diseases, or climate change). U. S. defense expenditures account for nearly...