power but seek hegemony for security because the anarchic makeup of the international system creates strong incentives for states to seek opportunities to gain power at the expense of competitors. Mearsheimer summarized that view in his 2001 book The Tragedy of Great Power Politics: Given the difficulty of determining how much power is enough for today and tomorrow, great powers recognize that the best way to ensure their security is to achieve hegemony now, thus eliminating any possibility of a challenge by another great power. Only a misguided state would pass up an opportunity to be the hegemon in the system because it thought it already had sufficient power to survive. He also dismisses democratic peace theory, which claims that democracies never or rarely go to war with each other. Mearsheimer does not believe it to be possible for a state to become a global hegemon (see section on Night watchman below). Although that is theoretically possible, there is too much landmass and too many oceans, which he posits as having effective stopping power and acting as giant moats. Instead, he believes that states can achieve only regional hegemony. Furthermore, he argues that regional hegemons attempt to prevent other states from gaining hegemony in their region since peer competitors would be free to roam and thus could interfere in the established regional hegemon's neighborhood. States that have achieved regional hegemony, such as the United States, will act as offshore balancers by interfering in other regions if the great powers in those regions cannot prevent the rise of a hegemon. Endorsement of E. H. Carr In a 2004 speech, Mearsheimer praised the British historian E. H. Carr for his 1939 book The Twenty Years' Crisis and argued that Carr was correct when he claimed that international relations were a struggle of all against all, with states always placing their own interests first. Mearsheimer maintained that Carr's points were still as relevant for 2004 as for 1939 and went on to deplore what he claimed was the dominance of "idealist" thinking about international relations in British academic life. Night watchman Night watchman in Mearsheimer's terminology is a "global hegemon", a theoretical impossibility according to The Tragedy of Great Power Politics. Nevertheless, in 1990, Mearsheimer mentioned the existence of a "watchman". Democracies lived at peace because "America's hegemonic position in NATO ... mitigated the effects of anarchy on the Western democracies and induced