Why was settlement on the great plains so difficult in the 1800s

the monroe doctrine is the best known u.s. policy toward the western hemisphere. buried in a routine annual message delivered to congress by president james monroe in december 1823, the doctrine warns european nations that the united states would not tolerate further colonization or puppet monarchs.

the united states broke it's neutrality was the constant german sinking of trading vessels resulting in the loss of lives, one example would be the lusitania.

d. both had been uninhabited before settlers arrived.

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