A lot of assumptions there. Just for sake of argument, let's say the Ark is unconvered in Antarctica, and looking at it doesn't kill you.
Where should it be displayed of the following three choices:
a) The Vatican
b) National Museum of Israel (or whatever it's called)
c) The Smithsonian Museum
wow - can you imagine the public bickering that would ensue? the finding country vs. israel and the various christian churches?
then imagine it is found by someone like china.
None of the above. The Vatican has no claim on the Ark of the Covenant...it belongs to religious Jews. Same goes for the museums. End of story.
Guess they're just gonna have to build a Temple.