This passport replaces the one I lost while exiting the Phoenix airport. With this document I can now update my British passport while my US passport sits expired.
Three citizenships. What does it mean? Aside from a potential career as spy for a secret global organization, it means I'm a part of three of the biggest membership clubs on earth. It's unbelievable the benefits they bring.
For the price of your annual taxes you get security services, access to land and other resources, health and education services, and so much more. They're often structured so that you can even join the leadership and set the direction for how the club spends its money.
My advice though is to try not to define your identity through any membership club, even substantial ones like citizenships.