Good Day pals, pls I would like any1 with useful information to enlighthen me. Am abt to apply for a US Visa and my frnd over there told me with an invitation 4rm d US Army, d visa is gaurnteed. Pls how true is dis??

I doubt this!

why would the u.s army send you an invitation? or are we talking about a solider sending you an invitation. in which case it would be a lie because any individual can send you an invitation and that persons employment might have an influence in you getting the visa but, i doubt if a solider sent you an invitation would guarantee the visa

If you were invited by the US army, it would be a matter of state affairs and possibly a diplomatic visa or waiver. You would certainly have to get clearance from Nigeria to be courting a foriegn military for business or otherwise. I am sure Nigeria has laws and concerns about international spying. Only if it were done as a matter of state affairs with Nigerian government knowing.

Any thing other than that is very suspicious. The US army cannot just invite any foriegner except as an official business of the government.
There is the fact that foriegners who enlist or get commissioned to the US military and serve a prescribed term of duty, automatically qualify for citizenship or we could say are invited to become citizens of the country they pledged to and served honorably.
But this can happen only for foriegners who enter the country legally and apply for military duty from within the USA.

Maybe there is a chance that the USA has grown desperate and changed and is feilding foriegn recruits out of foreign lands, but i have not heard about this, i would also suspect that they would be very careful which nations they draw service members from. They would draw from countries in well founded ally groups with USA, before they drew from Nigeria. USA is very sensitive about drawing from countries with terrorizm within the borders. They would hate to have a boko haram boy come over and enlist only to conduct mutiny and sabotage.

Maybe CIA would do something like OP mentioned, or similar sectors of military black ops and intelligence could try that. Still it is a risk without clearance from Nigeria government.

Please, there is no such thing. Just like @19nain said, if it is a military mission between the two government them you may not have any issues hence you pass all necessary clearance. Remember, such visa is negotiated by the state department throught the local embassy.

Now if your invitation is from an individual military officer them your case will be treated just as any other u.s citizen invitation letter, subject to approval or not approved.

If the above stated statement in secound paragraph is your true situation, them the burden is on you to prove your visa situation.

Remember the invitee fat salary or type of work wouldn't give you visa though psychological it seems if it helps. You need to prove you are a tourist and only coming for tourism or vacation purposes. You such most have a strong ties in your country of birth and so on, the burden to prove that all rest on you. Yes they will look at the invitation letter and other documents the invitèe gave you however, you have the strongest burden to prove you worth the visa.

Sponsorship works more when you, coming with a type of work visa or migrant type of visa, them the visa officer will look into details your sponsor such as marriage, nanny and other type of work visa.

Good luck though