Question:  Nile Gardiner is director of the Margaret Thatcher Center for Freedom at The Heritage Foundation, an American conservative think tank based where?
Context: The Heritage Foundation (abbreviated to Heritage) is an American conservative think tank based in Washington, D.C. The foundation took a leading role in the conservative movement during the presidency of Ronald Reagan, whose policies were taken from Heritage's policy study "Mandate for Leadership".  Heritage has since continued to have a significant influence in U.S. public policy making, and is considered to be one of the most influential conservative research organizations in the United States.  After the 2016 election of Donald Trump as U.S. President, Heritage leader Rebekah Mercer played a major role in shaping his transition team. The John Locke Foundation (JLF) is a conservative think tank based in North Carolina.  The organization was founded in 1990 to work "for truth, for freedom, and for the future of North Carolina."  It is named after the philosopher John Locke, who was a primary contributor to classical liberalism.  JLF was co-founded by Art Pope, a North Carolina businessman active in politics.  Pope's family foundation provides most of the support for the center. Heritage Action for America, more commonly known simply as Heritage Action, is a conservative policy advocacy organization founded in 2010.  It works with citizen activists nationwide to generate support for legislation in the U.S. Congress.  The organization has state operations in North Carolina and Pennsylvania and is a sister organization of the conservative think tank, The Heritage Foundation.  Heritage Action has been called a "powerhouse in a new generation of conservative groups" and "perhaps now the most influential lobby group among Congressional Republicans."  It is led by chief executive Michael A. Needham. The '"IMANI Center for Policy and Education"' is an African think tank based in Accra, Ghana.  As a member of the Atlas Economic Research Foundation, the think tank applies free market solutions to intricate domestic social problems.  It was founded in 2004 by Franklin Cudjoe, who currently serves as the president and chief executive officer.  The think tank's operations center on these four thematic areas: rule of law, market growth and development, individual rights, and human security and institutional development.  IMANI uses the Africanliberty.org platform as a springboard to reach out to the larger African audience in five international languages, including Swahili.IMANI exerts influence in the Ghanaian public education and policy sphere through media appearances, publications, research, and seminars.  The think tank is ranked by the Global Go To Think Tanks and Civil Societies Program, organized annually by the University of Pennsylvania.  According to the 2009 Index Report, IMANI was ranked fifth most influential in Sub-Saharan Africa, and the only African think tank to make the list of top 25 "Most Innovative" across the world. Edwin John "Ed" Feulner Jr. (born August 12, 1941) is president of the conservative think tank, The Heritage Foundation.  He served as president from 1977 to 2013.  His replacement, former U.S. Senator Jim DeMint, was named successor in late 2012 and took over as president on April 3, 2013.  Dr. Feulner is credited with establishing The Heritage Foundation.  When DeMint resigned in May 2017, the Heritage Foundation's board of directors unanimously elected Feulner as interim president. Dr.Wang, Huiyao (Henry) (; born July 2, 1958) is the Founder and President of Center for China and Globalization (CCG),the largest independent global think tank in China which has over 100 full-time researchers and working staff.  According to the "2016 Global Go To Think Tank Index" by the University of Pennsylvania Think Tank and Civil Society Program (TTCSP), the most prestigious think tank ranking in the world, CCG ranked 111th of the top world think tanks and was one of the world's top 40 independent think tanks.  TTCSP ranked CCG as the 7th top think tank in China and No. 1 independent think tank among the top Chinese think tanks.  Dr. Wang is also a top adviser to the Chinese government.  He was appointed as Counselor for China State Council by the Chinese Premier in 2015.  Dr. Wang is a well-known thought leader on China and globalization, China going global, Chinese global migration and talent flows, Chinese students studying abroad and returnees, and on global think tanks.  He is also a top adviser to international organizations such as World Bank, IOM and ILO as well as to global MNCs.  Dr. Wang has an impressive work career span over both Chinese and foreign governments, multinational executive, social entrepreneurial and academic fields. Luke Coffey (born 1979) is an American political adviser and US Army veteran.  Coffey formerly worked as a Special Adviser to Liam Fox, the ex-Secretary of State for Defence in the United Kingdom.  He is currently a Margaret Thatcher Fellow at The Heritage Foundation, an American conservative think tank. The Freedom Foundation of Minnesota (FFM) is a conservative think tank based in Minnesota.  The group states that it "actively advocates the principles of individual freedom, personal responsibility, economic freedom, and limited government."  Annette Meeks founded the organization in 2006 and currently serves as CEO.  The Freedom Foundation of Minnesota founded Minnesota Watchdog, an online news service.  The organization is a member of the State Policy Network. Caleb Crosby is an American think tank executive.  In 2014, he became president of the Alabama Policy Institute (API), a conservative think tank based in Birmingham, Alabama.  Crosby had previously served as API's vice president and chief financial officer.  Prior to joining the think tank, Crosby worked for the 2004 re-election campaign of George W. Bush.  He served in the George W. Bush administration at the Environmental Protection Agency and later at the White House, where he traveled with President Bush as a financial advisor.  Crosby also worked at the United States Department of the Treasury and as CFO of the National Republican Congressional Committee. Nile Gardiner is a British conservative commentator, director of the Margaret Thatcher Center for Freedom at The Heritage Foundation, and a former aide to British Prime Minister Margaret Thatcher.  He is also a commentator on U.S. and British television and a frequent contributor to the Fox News network, and the London "Daily Telegraph".  Gardiner is co-author with Stephen Thompson of the book, "Margaret Thatcher on Leadership: Lessons for American Conservatives Today" (Regnery 2013).
Answer: in Washington, D.C.