Most aren't submitted to Congress because they don't involve large expenditures - of money or personnel. They're usually negotiated by the State Department and the Pentagon.
But major agreements, such as the 1970 pacts controlling U.S. troops in the North Atlantic Treaty Organization, were ratified by the Senate. Half the country's pacts fall under the guidelines of the NATO agreement. The 1954 treaty controlling U.S. forces in South Korea also was ratified by the Senate.
More specifically, and as a 2008 Congressional Research Service report summed up, "Formal requirements concerning form, content, length, or title of a SOFA do not exist. A SOFA may be written for a specific purpose or activity, or it may anticipate a longer-term relationship and provide for maximum flexibility and applicability. It is generally a stand-alone document concluded as an executive agreement. A SOFA may include many provisions, but the most common issue addressed is which country may exercise criminal jurisdiction over U.S. personnel. Other provisions that may be found in a SOFA include, but are not limited to, the wearing of uniforms, taxes and fees, carrying of weapons, use of radio frequencies, licenses, and customs regulations.
"SOFAs are often included, along with other types of military agreements, as part of a comprehensive security arrangement with a particular country. A SOFA itself does not constitute a security arrangement; rather, it establishes the rights and privileges of U.S. personnel present in a country in support of the larger security arrangement. SOFAs may be entered based on authority found in previous treaties and congressional actions or as sole executive agreements."
Status of Forces agreements rarely get much attention outside of congressional, military and presidential policy circles. The Status of Forces agreement proposed in 2007 regarding U.S. forces in Iraq was different. It galvanized attention in the United States and Iraq because it came to define how and to what extent the United States would see its role in Iraq, while also defining to what extent Iraqi authorities would submit to American demands and exceptions to international law.
For a more detailed discussion of the controversy surrounding that proposed agreement, see Do Permanent US Bases in Iraq Mean a Permanent Occupation?
