Senator John McCain to Vladimir Putin -- Hand Over That Super Bowl Ring

Enough is enough ... Russian President and alleged Super Bowl ring snatcher Vladimir Putin needs to get that ring back on U.S. soil ASAP ... so says Senator John McCain.

Our photog caught up with Sen. McCain in Georgetown Sunday and broke down President Obama's chances of resolving the greatest threat to US-Russian relations since that thing in Cuba.

McCain -- a true American war hero (just sayin') -- says he's outraged and makes it clear ... the SB bling Putin took from New England Patriots owner Robert Kraft ... belongs back in the U.S. of A.

FYI --- Putin denies stealing the ring in 2005, his people say it was a gift. Riiiight.

So, can Prez O -- who's heading to Russia this week -- get it back? Check out JMC's take.