With the exception of a Head of State or Government who qualifies for an A-1 visa regardless of the purpose of the visit to the United States, the type of visa required by a diplomat or other government official depends upon the purpose of travel to the United States.
Government officials traveling to the United States to perform non-governmental functions of a commercial nature or traveling as tourists require the appropriate H, L or B visa, or if qualified, travel visa free under the Visa Waiver Program. They do not qualify for diplomatic or official visas for this purpose of travel.
Spouses, Partners and Children: Immediate family members are defined as the spouse and unmarried sons and daughters of any age who are members of the household. Individuals who do not qualify as immediate family members may be eligible to apply for B-1/B-2 visas. B-1/B-2 visa applicants are required to pay the MRV application fee, and reciprocal issuance fees, if applicable.