6h waiting time in Minneapolis airport, enough for a trip to Mall of America?

I'm European and on my flight back from Philadelphia to Europe I have almost 6h waiting time in Minneapolis airport (5h 50min). It is our return flight, so we have everything in order to travel inside the USA, I believe.

I've read that the Mall of America is pretty close and worth a visit. I come from Philadelphia, and the next flight is to Paris. Is 6h a safe enough margin to spare some time there? Is it worth it the 'risk'? Also, I've never used Uber, since it doesn't really work here in Europe (at least in Spain), is it safe enough to consider it over the Train or regular Taxi system?

Thanks in advance

EDIT: Some important info: It will be a Sunday, from 10:00 to 16:00