Legion Troll
A fine upstanding poster
A United Nations multilateral treaty defines who is a refugee, and sets out the rights of individuals who are granted asylum and the responsibilities of nations that grant asylum.
In the general principle of international law, treaties in force are binding upon the parties to it and must be performed in good faith.
Article 1 of the Convention, as amended by the 1967 Protocol, defines a refugee as:
"A person who owing to a well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion, is outside the country of his nationality and is unable or, owing to such fear, is unwilling to avail himself of the protection of that country; or who, not having a nationality and being outside the country of his former habitual residence as a result of such events, is unable or, owing to such fear, is unwilling to return to it."
"No Contracting State shall expel or return ('refouler') a refugee in any manner whatsoever to the frontiers of territories where his life or freedom would be threatened on account of his race, religion, nationality, membership of a particular social or political opinion" (Article 33(1)).
It is widely accepted that the prohibition of forcible return is part of customary international law. This means that even States that are not party to the 1951 Refugee Convention must respect the principle of non-refoulement.
The USA ratified the protocol in 1968.
https://en.wikipedia.org/wiki/Convention_relating_to_the_Status_of_Refugees#Application_Today