to the House of Representatives, serving there for 17 years, and Andrew Johnson returned to the Senate in 1875, though he died soon after. Some ex-presidents were very active, especially in international affairs, most notably Theodore Roosevelt; Herbert Hoover; Richard Nixon; and Jimmy Carter. Presidents may use their predecessors as emissaries to deliver private messages to other nations or as official representatives of the United States to state funerals and other important foreign events. Richard Nixon made multiple foreign trips to countries including China and Russia and was lauded as an elder statesman. Jimmy Carter has become a global human rights campaigner, international arbiter, and election monitor, as well as a recipient of the Nobel Peace Prize. Bill Clinton has also worked as an informal ambassador, most recently in the negotiations that led to the release of two American journalists, Laura Ling and Euna Lee, from North Korea. During his presidency, George W. Bush called on former Presidents Bush and Clinton to assist with humanitarian efforts after the 2004 Indian Ocean earthquake and tsunami. President Obama followed suit by asking Presidents Clinton and Bush to lead efforts to aid Haiti after an earthquake devastated that country in 2010. Clinton was active politically since his presidential term ended, working with his wife Hillary on her 2008 and 2016 presidential bids and President Obama on his 2012 reelection campaign. Obama was also active politically since his presidential term ended, having worked with his former vice president Joe Biden on his 2020 election campaign. Trump has continued to make appearances in the media and at conventions and rallies since leaving office. Pension and other benefits The Former Presidents Act (FPA), enacted in 1958, grants lifetime benefits to former presidents and their widows, including a monthly pension, medical care in military facilities, health insurance, and Secret Service protection; also provided is funding for a certain number of staff and for office expenses. The act has been amended several times to provide increases in presidential pensions and in the allowances for office staff. The FPA excludes any president who was removed from office by impeachment. According to a 2008 report by the Congressional Research service: Chief executives leaving office prior to 1958 often entered retirement pursuing various occupations and received no federal assistance. When industrialist Andrew Carnegie announced a plan in 1912 to offer $25,000 annual pensions to former Presidents, many Members of Congress deemed