The Monroe Doctrine of 1823 established which idea?

 President James Monroe's 1823  message to Congress contained the Monroe Doctrine, which warned European powers not to interfere in the affairs of the Western Hemisphere. Understandably, the United States has always taken a particular interest in its closest neighbors – the nations of the Western Hemisphere.

they required less loading and unloading

explanation:

the shipping container improved shipping because it cut down on unloading time by three weeks, eliminated wasted space, and allowed ships to carry.

to demand women’s suffrage