Final answer:
Legal restrictions serve as the main deterrent for American citizens working as migrant workers, in addition to concerns over cultural differences, language barriers, and economic impacts.
Step-by-step explanation:
The main deterrent for American citizens working as migrant workers is largely related to legal restrictions. Unlike internal movement between states and cities which is generally met with no legal barriers, when it comes to crossing national borders, some numerous laws and regulations can act as significant deterrents. These laws are designed to control immigration and can prevent citizens from easily seeking employment as migrants in other countries. Additionally, other concerns such as cultural differences, language barriers, and the impact of immigration on wages, income levels, and government taxes and spending are also factors that can influence decisions regarding migration for work.