An obvious defect in the united states' banking system that was exposed during the great depression was

Lack of Regulation

Explanation:

The great depression showed the world that the US financial system was largely unregulated, which made it have a trust problem. As a result of the depression, new efforts like the SEC were put in place to regulate the markets.

on april 6, 1917, the u.s. joined its allies--britain, france, and russia--to fight in world war i. under the command of major general john j. pershing, more than 2 million u.s. soldiers fought on battlefields in france.