Polls indicate that Americans believe that more of their tax dollars go towards humanitarian and development assistance than is actually the case. Less than 1% of the federal budget is devoted to humanitarian and development assistance. A recent poll shows that Americans would allocate about 15% of the federal budget to this area.
The graph below shows federal spending on international affairs (not including military assistance) compared to other parts of the federal budget. International affairs other than military aid includes humanitarian and development assistance; conduct of foreign affairs; foreign information and exchange activities; and international financial programs. General government includes the legislative branch; the executive branch; central fiscal operations, property management, and records management; other types of general government expenses (i.e., not related to a particular agency); DC and the territories. The Administration of Justice includes federal law enforcement activities; federal litigative, judicial, correctional, and criminal justice activities.
Source: Office of Management and Budget, Budget of the U.S. Government, FY2007 [1]; PIPA/Knowledge Networks Poll, The federal budget: the public's priorities [2], March 7, 2005.
Links:
[1] http://www.whitehouse.gov/omb/budget/fy2007/
[2] http://pipa.org/OnlineReports/budget/030705/Report03_07_05.pdf