As for Warthunder, not sure on how they will fair on the naval part BUT they do have a persistant map global "World War" mode brewing; with nothing said around it but i have a gut feeling it will look something simular towards WWIIONLINE / Heroes and generals map wise. And in WWIIONLINE i have spent 3-5 hours driving around as a destroyer / cargo ship to transport tanks in operations so thats always possible.
Biggest problems with those games are that they do not need subs as they fill no purpose since there is not a supply convoy system making them obsolete as they have no game :/
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