Passage: Between 1815 and 1914, a period referred to as Britain's "imperial century" by some historians, around 10,000,000 square miles (26,000,000 km2) of territory and roughly 400 million people were added to the British Empire. Victory over Napoleon left Britain without any serious international rival, other than Russia in Central Asia. Unchallenged at sea, Britain adopted the role of global policeman, a state of affairs later known as the Pax Britannica, and a foreign policy of "splendid isolation". Alongside the formal control it exerted over its own colonies, Britain's dominant position in world trade meant that it effectively controlled the economies of many countries, such as China, Argentina and Siam, which has been described by some historians as an "Informal Empire".British imperial strength was underpinned by the steamship and the telegraph, new technologies invented in the second half of the 19th century, allowing it to control and defend the empire. By 1902, the British Empire was linked together by a network of telegraph cables, called the All Red Line.

Question: What is the state of affairs called that Britain embraced?
Pax Britannica