British imperialism is the father of the modern West and Spanish imperialism is its mother. Before the Age of Imperialism, the West was not a global power. The Classical Greeks and the Romans were not global powers—they were powers in an Europe that was deeply divided and mired in unending wars and massacres. The West held some territories in the Levant and North Africa during the Ancient and the Middle Ages, but the empires of the Levant and North Africa too held territories in Europe for centuries.
The first teachers of the Romans, the Etruscans, were conquerors who had arrived from the Levant (according to Herodotus, they were from Anatolia). Carthage dominated the Spanish territories and Sicily for centuries. The Islamic powers dominated Spain till the fifteenth century. The Ottomans controlled Eastern Europe till the twentieth century. The barbarian tribes from central Asia controlled large parts of Europe during the time of the Roman Empire. The barbarian raids were a regular feature in Europe till the Middle Ages.
The modern West became wealthy and powerful during the Age of Imperialism. In 1945, the Age of Imperialism came to an end and the West started losing power. Without imperialism, the West cannot be a global power—I doubt that it can even be a European power for long.