What was the main message of the Monroe Doctrine? A. The United States and Great Britain formed a permanent alliance that permitted them free reign in the western hemisphere.
B. The United States would not interfere with European affairs and the western hemisphere was closed to further European expansion.
C. The United States and Europe would no longer be allies except when fighting against the Barberry pirates.
D. The United States isolated itself from all populations and all U. S boarders were closed for immigration.