Answer: all of the above
Increased globalization has been possible, because (in the words of New York Times journalist, Thomas Friedman) the world has become flatter. Thus, due to technological advances and reduction of barriers companies have increasingly become
Generally speaking, from the 1830s on, people hoping to settle in the Northwest "B-traveled along the Oregon Trail," since this had become a well-established route.
The Iraq War did not end quickly because the U.S. Government specifically the State and Defense Departments did not have a clear exit strategy. Following civil unrest in Iraq as well as increasing attacks on U.S. soldiers and the newly formed Iraqi Government the U.S. Government was unable to withdraw quickly and suffered large casualties and expended hundreds of billions of dollars in resources.
Economics
The treasure fleet voyages cost Ming China vast amounts of
money and brought nil returns since they were not trade excursions but only
brought back exotic novelties. As a result, the government recovered little of
the cost. Moreover, China was self-sufficient and did not need anything from
the Indian Ocean countries
