Precisely. Why didn't he off himself before he even got on the plane? Or why didn't he wait until he had returned to Maryland?
In the travel time from Lisbon to Newark, what could have changed his state-of-mind?
Why couldn't it have waited until he returned home? Choosing to act within such a limited time frame, between the gate and customs, under a circumstance that could not possibly have been convenient (how does one go about hanging oneself in a janitor's closet?), strongly suggests something is rotten in the state of EWR.
Maybe he had just broken up with a fiance in Portugal, or something sad like that.
However, it's such an odd place for a suicide. How did he know the cleaning lady wouldn't come back before he finished the job?
Now, what if...you were an Al Quaeda agent who was supposed to BLOW UP that plane after it left Portugal, and you got cold feet, and you couldn't do it, because you were still halfway human.
Are the Jersey Jihadists at it again?