A scene from “Unfinished Business”

Louis Mountbatten: Gentlemen. In the past decade alone, I have, by my reckoning, been in seventy-three coups in forty-six different countries around the world. And the success of some of these might encourage us. In Ghana, two years ago, President Nkrumah was ousted with just 500 men. And in 1961, South Korea, Major General Park Chung Hee seized power with 3500 men. And in 1964, Gabon, just 150 men were able to arrest President M'Ba, and thus gain control over the levers of state power. And, of course, it was with just one Legion that Caesar crossed the Rubicon. Perhaps we would not seek to follow his fate. Sic Semper Tyrannis, gentlemen. Now, what all successful insurgencies have in common are five key elements: control of the media, control of the economy and the capture of administrative targets, for which you'd need the fourth element, the loyalty of the military. Now, in Ghana and Gabon, this could be achieved with a handful of battalions, but here, in the United Kingdom? We would need to secure Parliament, Whitehall, Ministry of Defense and the Cabinet Office. Prime Minister would be arrested, of course, along with other politicians still loyal. Then we'd have to shut down the airports, air traffic control. Same with the train stations. Curfews would be put in place, Martial Law declared. And I haven't even mentioned the police. It would take tens of thousands of unquestioningly loyal servicemen, and even in my heyday, I could never command that. Which brings me to the fifth element: Legitimacy. Now, our government draws its strength from long-established institutions that support it. The courts, body of common law, the Constitution. For any action against the State to succeed, you'd have to overthrow these as well. But in a highly evolved democracy such as ours, their authority is sacrosanct. Which is why, gentlemen, a coup d'etat in the United Kingdom doesn't stand a chance.