If there are three books everyone wanting to improve their understanding of the world we live in I suggest the following three books!
Why Nations Fail: James Robinson and Daron Acemoglu, a brilliant book which seeks to define what is the common thread that attatches itself to succesful states. It does this by exploring a plethera of different societies, extremely good if you want to develop the breadth of your historical understanding. It arrives at the conclusion that systems that offer socio-economic power to a diverse section of society are succesful in keeping people functional within that state.
Clash of Civilisations: Samuel Huntington, a breathtaking exploration of a theory that divides the world into a new ‘clash’ of major civilisations. It has been important in shaping my understanding of contemporary news and objectives in the modern world. While the debate on whether he is right or not provides hundreds of pieces of secondary reading that will engage you further in modern world politics.
Sapiens: Yuval Noah Harari, again a book that offers interesting social commentary, and really shows fundamental laws and institutions of all civilisations on earth. Through his understanding of what makes humanity unique, we can understand what different civilisations (if you believe Huntington) find close to their heart. Its also a humbling book that really puts into perspective how fresh civilisation really is.