The most important reasons go back to the differences between the English colonial heritage in North America, and the Spanish/Portuguese colonial heritage in South America.

Although England, Spain and Portugal were all monarchies during the colonial period, and even today, England had "Republican" and "Democratic" traditions going back for centuries. This started with the Magna Carta in 1215, and continued with the (English) Bill of Rights in 1689, that limited the power of the king, and gave power to elected legislators. These documents led to American Constitution and Bill of Rights. Basically, North American people were relative content with the their governments because they felt that they were fairly represented.

There were no counterparts in Spanish history to these limitations on royal power, and the imposition of "popular" power through elections. This meant that English colonial rule was milder and less centralized than that of Spanish colonies, during the colonial period, which led to more democratic and less authoritarian societies in North America, even after the independence movements.

The most important reasons go back to the differences between the English colonial heritage in North America, and the Spanish/Portuguese colonial heritage in South America.

Although England, Spain and Portugal were all monarchies during the colonial period, and even today, England had "Republican" and "Democratic" traditions going back for centuries. This started with the Magna Carta in 1215, and continued with the (English) Bill of Rights in 1689, that limited the power of the king, and gave power to elected legislators. These documents led to American Constitution and Bill of Rights. Basically, North American people were relatively content with the their governments because they felt that they were fairly represented.

There were no counterparts in Spanish history to these limitations on royal power, and the imposition of "popular" power through elections. This meant that English colonial rule was milder and less centralized than that of Spanish colonies, during the colonial period, which led to more democratic and less authoritarian societies in North America, even after the independence movements.

Another issue was that the Spanish colonies were established as money-generating (gold and silver) entities, almost from the get-go, which is to say that they were heavily taxed. On the other hand, British colonies were established largely to transfer malcontents from the British Isles to the New World, and were not seen as sources of tax revenue until the 1760s, which is to say that the English colonies had much more freedom to develop economically.