It wasn't necessary to invent an entirely fake challenge for the basis of this concept, but Phil Pauley Interactive went and did it anyway. It's the Transatlantic Seafloor Research Challenge, and (if it existed) it would promote oceanic research by tasking submarines equipped with wheels or tank treads to drive all the way across the Atlantic ocean, because why not?
Incidentally, the Germans tried to build submersible tanks to invade England via the English Channel during WW2, but it didn't work out very well. Modern tanks can ford deep rivers and (with minor modifications) even submerge completely, but you're not likely to see them crossing the Atlantic anytime soon. 'Course, you're not likely to see this thing crossing the Atlantic anytime soon either, because it's just a concept, and it still needs a bunch of tweaks before it's ready for production. You know, like guns. Big guns, lots of them, to fend off sharks and giant squid.
And also, lasers.