World policeman USA?

The USA is a superpower and superpowers primarily pursue their own interests by securing and/or expanding their power. This also happens to avoid that challengers do not emerge to dispute their power. The means are diplomacy, armaments and military interventions. The USA promises its friendly states protection from these global and regional competitors, who are often perceived as aggressive. The USA has earned a good reputation in history in this respect. They helped the Europeans defeat aggressive states in both world wars. They acted as a protective power in the “East-West conflict” against communism. Success was highlighted by nuclear deterrence and rearmament in the Korean hot war of 1950-1953 and the Cold War.
In order to enjoy protection against communism, the friends of the USA accepted a lot. They saw the atomic bombing of Japan as justified. They looked away of the atrocities committed by the GIs in the – ultimately lost – war in Vietnam. Despite claiming to be a leading power of free-market democracies against communist dictatorships, it was okay for the Europeans when the US overthrew democratically elected governments in Iran in 1953 and in Chile in 1973. After the end of the Cold War, Western states continue to seek the protection of the USA, for example in NATO in Europe against Russia or other alliances such as the AUKUS (with the USA, Great Britain and Australia) and the Quad (with the USA, Great Britain, Japan and India) in Asia against China.
However, the US-led interventions such as in the Balkans in the 1990s, in Afghanistan after 2001, in Iraq in 2003 and in Libya in 2011 did not leave behind any stable situations. Confidence in the USA began to crumble. Russia was not deterred by the USA from invading Ukraine. Diplomatically, China and small Qatar were more successful in the Middle East. The friendly Arab states are fulfilling less and less of the US’s wishes, for example to increase their oil production und limit their relations with China. Even Israel could not be persuaded to respect humanitarian law in Gaza in order to release American hostages. The BRICS countries (Brazil, Russia, India, China, South Africa and the other new members) form their own, albeit heterogeneous, power with more than thirty percent of global economic production and forty-five percent of the world’s population. Trade between them is often conducted outside the dollar in national currencies.
The US’s own interests and those of friendly states are no longer as congruent as they were during the Cold War. The states of the Global South in particular no longer want to rely entirely on the USA’s promises of protection. It goes without saying, that the US will remain an important – if not the most important – actor in world politics.