Secretary of State for Defense

In the UK, Her Majesty's Principal Secretary of State for Defence (Defence Secretary) is an official within Her Majesty's Government and head of the Ministry of Defence.

The office is a British Cabinet level position and is one of the 5 key ministries of a Western style government.

The UK's minister was Sir Michael Fallon (as of May 2017) and the USA's minister was James Mattis (as of May 2017).

The minister has responsibility for defending the nation, going to war with another nation, looking after the military, helping in disaster relief, spying on foreign nations and helping quash armed uprisings in their homeland.