A global federal government would be a mighty instrument – and lots of power-hungry leaders and groups from around the planet will no doubt vie with each other to manipulate it to their parochial ends. The global institutions will therefore need to incorporate robust mechanisms to ensure that they remain rigorously accountable, fully transparent, and genuinely independent and impartial in their basic functioning. Four features would therefore be important to include in such a government: strong subsidiarity, the separation of powers, an executive branch with plural leadership, and a high bar of supermajority voting before major action can occur in the world legislature. A second key goal for this government will be to reduce the gross disparities in wealth and opportunity that divide the world’s peoples. One plausible mechanism for achieving this would be a UN-run system of Guaranteed Minimum Income, implemented globally. Such a government could also adopt pragmatic policies to nudge the world’s autocratic nations toward higher degrees of democratization and respect for human rights.

Any government that wants to be taken seriously needs teeth. This chapter sketches a global security system in which national governments will still play a key role, but in which they have also worked together to create stable mechanisms of collective security. Since it is impossible to coerce nuclear-armed Great Powers through direct military action, the new global security system will need an especially robust regime of economic sanctions. If a Great Power transgresses international laws in egregious ways, such sanctions would aim to persuade the leaders of that nation that the costs of continued violations greatly exceed the benefits. In extreme cases, such sanctions could also aim to destabilize a transgressor nation’s economy so severely that its citizens would be impelled to bring about regime change from within. If such a global security system were in place for many decades, successfully keeping the peace, then incremental steps toward reductions in standing armies could be gradually undertaken. The resulting “peace dividend” could be used to further reduce global economic disparities, and to help fund the technologies for mitigating climate change.

This chapter describes a “second wave” of modifications to the UN system that would further strengthen its capabilities during the latter half of the twenty-first century. It focuses on two major challenges that the UN will be facing during the coming decades: the international regulation of biotechnology, and the global effort to remove excess carbon dioxide from the Earth’s atmosphere. New, CRISPR-based technologies for editing genomes have allowed scientists to make path-breaking innovations, bringing the concept of “designer babies” far closer to realization than ever before. At the same time, the climate crisis has prompted some scientists to propose radical new forms of “solar radiation management” such as artificial clouds or even a space shield to prevent runaway global warming. Effective regulation of such extreme new technologies will require new international instruments over the coming decades, such as a democratically elected World Parliament, a more representative Security Council, and a standing UN army equipped to respond swiftly to emerging crises.