Why is turner’s frontier thesis still debated today?

Turner thought that the moving frontier line (having two people or more in a square mile) was going to affect future America and its pioneer's. Some people still agree with him and some people don't. It really can go either way because it has damaged and helped American's in the long run.

zheng he was a chinese explorer who lead seven great voyages on behalf of the chinese emperor. his seven total voyages were diplomatic, military, and trading ventures, and lasted from 1405 – 1433. however, most historians agree their main purpose was to promote the glory of ming dynasty china.

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