Coming up with this off the top of my head for you but here you go:
I would say colonialism comes from a countries need to project itself beyond. natural borders
And of course, the more land you control, the more room you have for increasing the population, building ports, and building the economy
As in rice, sugar cane, wheat, barley, cotton, spices and sometimes even people (unfortunately)
The triangle trade was a route used by Britain which allowed them to send and produce textiles and manufactured goods to colonies in Africa
While they were there they would take the native Africans and send them to the americas to work plantations
On these plantations they would collect cash crops and bring them back to Europe so they could complete the route and repeat it
And yes that’s terrible but because of this, they could project themselves over these areas of the world and like mentioned before, build the population, build ports and infrastructure, and expand the economy
So to wrap up, colonialism is the need to expand past natural borders in hopes of power, prestige, and wealth
