How was the american civil war part of a global trend toward more destructive and deadly wars?

The correct answer to this open question is the following.

The American Civil War was part of a global trend toward more destructive and deadly wars in that it equals the total number of US citizens who died in all the other wars, from the Revolutionary War until the War of Iraq.

According to historians, the number of people that die during the bloody Civil War reached an impressive number of 620,000. Most of them died on the battlefield but many others died of diseases. Just for comparison purposes, the number of soldiers that died during World War 1 was approximately 116,000 and in World War II, 405,000. Want to know how many died in the Vietnam War? Approximately 58,000.

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four sitting presidents have been assassinated while in office but the first was abraham lincoln,