Well, Dr. Alan Lew, Northern Arizona University reports in his blog that the World Travel and Tourism Council is again going to try to "prove" the title statement. Read his blog for the details.
I mean, can tourism be bigger that the medical field? Just look at your latest EOB (Explanation of Benefits) from your health insurance.
You've heard about the military spending $1,000 for a hammer, but what about $100 for an aspirin.
Wow, thinking about that, perhaps the military is the largest industry in the world?