What restrictions are there on immigration today?

Found this off of google, "Intolerance toward immigrants from southern and eastern Europe resulted in the Immigration Act of 1924, which placed a numerical cap on immigration and instituted a deliberately discriminatory system of national quotas. In 1965, the United States adopted a new immigration law which ended the quota system."

Hope this helps, have a great day and stay safe! :) :D :3

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.

union blockade

explanation:

the union blockade in the american civil war was a naval strategy by the united states to prevent the confederacy from trading.

the blockade was proclaimed by president abraham lincoln in april 1861, and required the monitoring of 3,500 miles (5,600 km) of atlantic and gulf coastline, including 12 major ports, notably new orleans and mobile. those blockade runners fast enough to evade the union navy could only carry a small fraction of the supplies needed. they were operated largely by british citizens, making use of neutral ports such as havana, nassau and bermuda. the union commissioned around 500 ships, which destroyed or captured about 1,500 blockade runners over the course of the war.