Mearsheimer is best known for developing the theory of offensive realism, which describes the interaction between great powers as being primarily driven by the rational desire to achieve regional hegemony in an anarchic international system.

"[16]: 87  Moreover, Liddell Hart's limited attempts to operationalize the theory clearly indicated that what he primarily had in mind was to "indirectly" defeat a continental adversary by "break[ing] the morale of the enemy's civilian population, not to destroy his military forces, which of course is what the blitzkrieg is concerned with".

Not surprisingly, Liddell Hart was proven utterly wrong on the fundamental military questions of the interwar period (he dismissed the possibility of a decisive German offensive in the Western front) and fell into disrepute in the immediate aftermath of the war.

[16]: 43 Mearsheimer shows that Liddell Hart managed to salvage his intellectual stature by convincing former Wehrmacht generals to credit him with the ideas that led to the development of Germany's blitzkrieg strategy.

Eager to restore their own tarnished reputation after the war, retired German generals such as Heinz Guderian allowed Liddell Hart to exaggerate his influence on blitzkrieg in their memoirs in exchange for helping them promote an image of themselves as having been military innovators first and foremost rather than Nazi henchmen.

For example, the founder of the Israel Defense Forces Operational Theory Research Institute, Simon Naveh, concurred in a separate study, which found that "by distorting the actual historical circumstances of the Blitzkrieg formation [Liddell Hart] obscured its temporal and cognitive origins....

The early-1950s display of the transformed version of Blitzkrieg as a historical fact, carrying the joint signature of Liddell Hart and Guderian, lent it an authentic touch and a professional legitimacy that could not be shaken.

"[18]: 803 In 1990, Mearsheimer published an essay in which he predicted that Europe would revert to a multipolar environment, similar to that of the first half of the 20th century, if American and Soviet forces left after the end of the Cold War.

When challenged on the former assertion at a lecture given to the International Politics department at the University of Wales in Aberystwyth, he maintained that in spite of European integration and expansion, he still believed that his predictions would come true if the US military left Europe.

"[25] Mearsheimer charges that "a careful look at Keohane and Martin's response reveals that liberal institutionalism in its latest form is no longer a clear alternative to realism, but has, in fact, been swallowed up by it.

The structural theory, unlike the classical realism of Hans Morgenthau, places the principal emphasis on security competition among great powers within the anarchy of the international system, not on the human nature of statesmen and diplomats.

Mearsheimer's theory of offensive realism has become a popular explanation of the American strategic approach in resisting China as a growing superpower that might one day unseat America's dominant position.

"[32] In January and early February 1991, Mearsheimer published two op-eds in the Chicago Tribune and the New York Times and argued that the war to liberate Kuwait from Iraqi forces would be quick and lead to a decisive US victory, with less than 1,000 American casualties.

[33][34] In March 2006, Mearsheimer and Stephen Walt, the former academic dean and professor of international relations at the Harvard Kennedy School, published a working paper,[35] as well as a London Review of Books article,[36] discussing the power of the Israel lobby shaping the U.S. foreign policy.

Panicked Jewish leaders, he argues, have turned to Zionism (blind loyalty to Israel) and scaremongering (the threat of another Holocaust) to keep the tribe united and distinct from the surrounding goyim.

[53] Additionally, he maintains that the US will attempt to form a balancing coalition that consists primarily of India, Japan, the Philippines, South Korea, Vietnam, and Indonesia to counter the growing strength and power projection capabilities of China.

In accordance with the theory's structural logic, China will pursue regional hegemony not because its domestic politics or ideology inclines it toward aggression but because "domination offers the best way to survive under international anarchy".

[55]: 374–375 In a subsequent debate with former US National Security Advisor Zbigniew Brzezinski in Foreign Policy magazine, Mearsheimer clarified, "It is unlikely that China will go on a rampage and conquer other Asian countries.

However, contrary to realist logic, the US in the post-Cold War period had "promoted investment in China and welcomed the country into the global trading system, thinking it would become a peace-loving democracy and a responsible stakeholder in a US-led international order".

To the contrary, Chinese leaders view liberal values as a threat to their country's stability, and as rulers of rising powers normally do, they are pursuing an increasingly aggressive foreign policy.

"[58] By contrast, Executive Director Tom Switzer of the Sydney-based Centre for Independent Studies opined in May 2020, "Rarely in history has an academic been as intellectually vindicated as John Mearsheimer, [He] accurately foresaw the intense Sino-American security competition that the coronavirus crisis has exposed.

"[62] Mearsheimer notes that Chinese interlocutors often challenge him on his assertion of China's unpeaceful rise, with some elites citing economic interdependence theory to dispute his realist views.

For example, he maintains that US President Franklin D. Roosevelt lied about the Greer incident in September 1941 because he was deeply committed to getting America into World War II, which he thought was in its national interest.

Since the mid-1990s, Russian leaders have adamantly opposed NATO enlargement, and in recent years, they have made it clear that they would not stand by while their strategically important neighbor turned into a Western bastion.

[71] They rejected his description of the Ukrainian revolution as a "coup", countering that "after police killed scores of demonstrators in downtown Kiev, the whole country turned against him [Yanukovych], effectively ending his political career.

[72] Political scientist Filip Kostelka said Mearsheimer "ignores the fact that Ukrainians – like other Eastern Europeans – have been actively seeking NATO membership to protect themselves from the Russian threat.

[74] Political scientist Filip Kostelka said "By publicly defending his scientifically unsound thesis, Mearsheimer legitimizes Russia's propaganda and violates the fundamental values of social responsibility that all academics should respect".

[73] Kostelka also said that Mearsheimer "remained oblivious to Russia’s numerous lies on public record, including Putin's original denial of any involvement in Crimea in 2014, which was followed by open boasting about the annexation a few months later".

[84]: 30  In particular, US-led efforts to expand the order's membership by spreading democracy were bound to backfire by provoking nationalist resistance, embroiling the US in disastrous military adventures, and stoking hostility among rival powers such as Russia and China.

They declared that "by providing rhetorical support for the exclusion of Jews, her words helped make the disreputable reputable, the indecent decent, the uncivilized civilized, and the unthinkable thinkable.