thereby convincing weaker states that it was more interested in cooperation rather than domination. U.S. strategic restraint allowed weaker countries to participate in the make-up of the post-war world order, which limited opportunities for the United States to exploit total power advantages. Ikenberry notes that while the United States could have unilaterally engaged in unfettered power projection, it decided instead to “lock in” its advantage long after zenith by establishing an enduring institutional order, gave weaker countries a voice, reduced great power uncertainty, and mitigated the security dilemma. The liberal basis of U.S. hegemony—a transparent democratic political system—has made it easier for other countries to accept the post-war order, Ikenberry explains. “American hegemony is reluctant, open, and highly institutionalized—or in a word, liberal” and “short of large-scale war or a global economic crisis, the American hegemonic order appears to be immune to would-be hegemonic challengers.” Michael Beckley argues American primacy is vastly underestimated because power indices frequently fail to take into account GDP per capita in the U.S. relative to other purportedly powerful states, such as China and India. In 2011, Barry Posen argued that unipolarity was in wane and that the world was shifting towards multipolarity. In 2019, John Mearsheimer argued that the international system was shifting from unipolarity to multipolarity. In 2022, William Wohlforth argued that the international system was heading towards a system that can be characterized neither as bipolarity nor multipolarity. He added that polarity did not appear to matter as much in the current international system, as great powers command a far smaller share of power vis-a-vis the rest of the states in the international system. Bipolarity Bipolarity is a distribution of power in which two states have a preponderance of power. In bipolarity, spheres of influence and alliance systems have frequently developed around each pole. For example, in the Cold War of 1947-1991, most Western and capitalist states would fall under the influence of the US, while most Communist states would fall under the influence of the USSR. Kenneth Waltz's influential Theory of International Politics argued that bipolarity tended towards the greatest stability because the two great powers would engage in rapid mutual adjustment, which would prevent inadvertent escalation and reduce the chance of power asymmetries forming. Dale Copeland has challenged Waltz on this, arguing that bipolarity creates a risk for war when a power asymmetry or divergence happens. Historic examples of bipolarity include