Washington, DC -based “The Heritage Foundation” strives to build an America where freedom, opportunity, prosperity and civil society flourish. Its mission statement reads: “Founded in 1973, The Heritage Foundation is a research and educational institute – a think tank – whose mission is to formulate and promote conservative public policies based on the principles of free enterprise, limited government, individual freedom, traditional American values, and a strong national defense.”
The Foundation claims it has influenced many policies and decisions in American history and polity and continues to do so. As it says: “We believe that ideas have consequences, but that those ideas must be promoted aggressively. So, we constantly try innovative ways to market our ideas.”
To read more about the foundation and its activities, logon to:http://www.heritage.org/

So we are talking of think tanks. Wikipedia says: “Since “think tank” is a term that has only found use since the 1950s, there is still some debate over what constitutes the first think tank. One candidate is the Fabian Society of Britain, founded in 1884 to promote gradual social change. The Brookings Institution, founded in the US in 1916 is another candidate for the first think tank. The term think tank itself, however, was originally used in reference to organizations that offered military advice, most notably the RAND Corporation, formed originally in 1945.
Until around 1970, there were no more than several dozen think tanks, mostly focused on offering non-partisan policy and military advice to the United States government, and generally with large staffs and research budgets. After 1970, the number of think tanks exploded, as many smaller new think tanks were formed to express various partisan, political, and ideological views.”