Müller was chairman of the Junge Union's Bavarian section from 1987 until 1991. In this position, his calls in favour of capital punishment for drug dealers caused significant controversy. Between 1989 and 1994, Müller was a Member of the European Parliament, where he served on the Committee on Transport and Tourism and on the Joint Assembly of the Agreement between the African, Caribbean and Pacific States and the European Economic Community. Since 1994, Müller has been a member of the German Parliament following the federal election that year. He served on the committees for foreign and defense policy and was the spokesman on Europe, foreign, and development policy for the CSU group.
From 2005 to 2013, Müller served as Parliamentary State Secretary at the Federal Ministry of Food, Agriculture and Consumer Protection under ministers Horst Seehofer and Ilse Aigner in the first and second cabinets of ChancellorAngela Merkel. In this capacity, he was responsible for international relations, third-world development projects, and world food aid programs, among other issues. In 2011, he participated in the first joint cabinet meeting of the governments of Germany and China in Berlin; his counterpart in the Chinese government at the time was Han Changfu. Following the 2013 federal elections, Müller was part of the CDU/CSU team in the negotiations with the SPD on a coalition agreement.
In April 2014, Müller became the first member of Chancellor Angela Merkel's cabinet to publicly confront world football's governing body FIFA over its allocation of the 2022 FIFA World Cup to Qatar, criticizing that the choice contradicted global efforts to tackle climate change and that human rights breaches on the country's stadium construction sites even extended to "slave labor." Later that year, he publicly accused Qatar of funding Islamic State militants, arguing that the country was the "keyword" when it comes to IS financing. In June 2017, Müller voted against Germany’s introduction of same-sex marriage.
International agriculture
Müller is strongly in favor of extending subsidizing German agriculture for export, which he hopes will lessen the flow of refugees coming to Europe
Relations to the African continent
Müller has in the past voted in favor of German participation in United Nations peacekeeping missions as well as in United Nations-mandated European Union peacekeeping missions on the African continent, such as in Somalia – both Operation Atalanta and EUTM Somalia –, Darfur/Sudan, South Sudan, Mali the Central African Republic, and Liberia. He abstained from the vote on extending the mandate for Mali in 2016. During an official visit in 2019, Müller described the slaughter of some 65,000 Herero and 10,000 Nama tribespeople in Namibia between 1904 and 1908 as genocide, one of the most senior government members to use the term while compensation claims were under discussion.
