10 Most Expensive Wars In U.S. History

This story was originally published by 24/7 Wall St. Declared an official holiday in 1971, Memorial Day honors those who have given their lives in service to the United States. While the human toll is always great, wars also cost treasure as well as blood. Many factors can affect the cost of waging war. Using a report from the Congressional Research Service, 24/7 Wall St. reviewed the most expensive wars in U.S. history. While the Mexican-American War cost just $2.4 billion, or 1.4% of GDP in 18...