 Complete the following phrase:  The United Kingdom was the worlds foremost power during the 19th and early 20th centuries, most notably during the so-called Pax Britannicaa period of totally unrivaled supremacy and unprecedented international peace during the mid-to-late 1800s. The country continued to be widely considered a superpower until the Suez crisis of 1956, and this embarrassing incident coupled with the loss of the empire left the UKs domit role in global affairs to be gradually diminished. Nevertheless, the United Kingdom remains a great power and a permanent member of the United Nations Security Council, a founding member of the G7, G8, G20, NATO, OECD, WTO, Council of Europe, OSCE, and the Commonwealth of Nations, the latter being a legacy of the British Empire. The UK had been a member state of the European Union and a member of its predecessors since 1973. However, due to the outcome of a 2016 