Does the immigration department need a background check before going to the United States for a visa?

All applications for immigration and naturalization in the United States require background checks.

Immigration background investigation is relatively simple, just check whether the reasons for birth and application are true. If you are naturalized, the background check will be very troublesome, and the previous situation will be checked (of course through special channels).

Visa refers to the procedure of endorsement and seal of passports or other travel documents held by domestic or foreign citizens by the sovereign organs of a country to show that they are allowed to enter, exit or transit. It can also be said that it is an endorsement certificate issued to them. Generally speaking, a visa is a document issued by a country's entry-exit administration (such as immigration bureau or its embassy or consulate abroad) to approve the entry of foreign citizens.