The Force Awakens already has beaten Titanic's original box office run of $1.8 billion. I don't think it's fair to count multiple re-releases vs. a movie that's only had one run. So for original runs TFA (2015/16) > Titanic (1997/98), both in the US and globally.
And yes Titanic DID benefit from China, the 3D re-release was in China a few years ago and did a lot of business there.
Inflation adjusted yes Titanic beats any modern movie including Avatar, but the original 1977 Star Wars (A New Hope) in that case beats both of them rather easily.
So this is kinda an iffy comparison, Star Wars has its own things to crow about where it does beat Titanic.
TFA will eventually get a re-release, it will only have to earn in the neighborhood of $130 million or so worldwide most likely to beat Titanic's overall total, which should be fairly easy. Disney should hold off some deleted scenes and they'll be able to hit that easy in a re-release.
