The author tries to understand through the whole book whether or not the UN has improved the international scenario since 1945 and to do so, he tries to imagine a world without it, through counter factuality, through mental simulations and “opposing worlds”.
In the first part of the book, the author meticulously probes some of the pathologies that afflict the organization born from the ashes of the Second World War. The limits identified are undoubtedly embedded, first of all, in the brakes imposed by the reluctance of the member states to surrender their sovereignty, wanting to remain anchored in the international design enshrined in the Peace of Westphalia of 1648. Added to this is the anachronistic debate on the division between a northern and a southern theatre of the world which, as Weiss claims, using a different and interesting interpretative lens, has in reality been replaced, since the end of the Cold War, by a fracture between East and West. Moreover, the structure of the UN is in no way that of a society or a hierarchical pyramid organization. It has numerous command centres scattered throughout the world, various strategic nodes such that some analysts define it as ‘organized anarchy’. The system lacks a central structure of authority. Furthermore, it has difficulties in the exercise of its leadership, suffering the deterioration of its dependence, of its integrity and of its own competence.
In the second part, Weiss sets out three examples to make the reader understand how much UN action has impacted the global scene and how much effort has been made to shape the world through its action. According to the author, the world would be more violent without UN action and it is enough to think only of peacekeeping. This was the means through which the organization was able to deploy forces in the field in a neutral manner without compromising the international system, during the Cold War since the first use of Blue Helmets in the Suez Crisis of 1956. The world would have been even more repressive and less welcoming and Weiss says so in clear terms, showing how decolonization could not have taken place without the precious help of the UN; today we would not even have the Universal Declaration of Human Rights, perhaps the organization’s greatest contribution in the field; we could not have seen the implementation of some deeply important principles such as ‘responsibility to protect’ (R2P). Finally, the world would certainly have been poorer and more polluted without the UN: it has in fact produced over the years an infinite amount of data and analysis but above all it has shared them with the world, giving everyone the opportunity to enjoy a general mapping. It has contributed to eradicating infectious diseases and other health threats and has intervened on climate change.
In light of all this, in the following chapters of the third part of the book, Weiss analyses what improvements could be made on the organisational level to ensure that the structure really does work, regardless of the short-sightedness of the Member States. In this section of the book, the author also offers a distinction between ideas and operations that allow us to reflect on theory and practice. It would have been a more repressive world if the UN had not intervened in a matter of human rights and through humanitarian operations. Beyond the undoubted successes and achievements, Weiss intelligently and objectively focuses the final pages of the work on the possible and absolutely necessary reforms that the organization should address. Because much has been done, but much remains to be done, and the UN today, especially with Trump’s United States, is facing a tough process of downsizing, with budget and contribution cuts. What we need to be very careful about is not making the organisation an appendix to the foreign policy of the Member States and, from this point of view, a reform of the Security Council, with a formula that goes in the direction of the multipolar world in which we now live, and of the structure of peacekeeping, appear to be extremely necessary and urgent.
There are five challenges facing the UN before it takes the path of change.

The challenge of ‘competition’ because the UN is becoming less and less funded and less important.
That of ‘consistency’ in its actions and methods.
‘Co-optation’ or the use of the multilateral system as an appendix to bilateral assistance that has made the UN a subcontractor of donor priorities.
That of its ‘capacities’: what is the UN really capable of doing? Repeating the strategies of the past would be a big and unforgivable mistake.
Finally, that of ‘complacency’ because too many international actors do not recognize the criticality of the situation and pretend nothing.

Weiss concludes this long and interesting debate on the usefulness of the UN with a look at the Trump era, and at the challenges that the world poses today to the organization that most of all has tried to secure the entire world, doing everything possible to avoid the escalation of violence or the outbreak of a new conflict. The answer to the question of the title is in the pages of the book, in the ideas and reforms proposed by the author, in which one grasps the will to ask the organization to rediscover its original idealism, its independence, its self-denial and its original coherence, which have made the UN the greatest attempt to build a world government, never thought of in the history of humanity