"Are you Batman?"
"I am Batman."
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And with those words, and William's subsequent Facebook clip, the Internet responded to that Bat-signal like japing crusaders, meme art and #BatTrump hashtags at the ready.
Now sure, it's tough to picture Trump trading his navy blazer for a purple-black cape, and so the Internet spasmed with laughter, giddy over this political theater of the absurd. And yet - yes, and yet - is Donald Trump really so different from fellow moneyman Bruce Wayne?
To peer beneath their masks for a moment, here are 15 Ways In Which Trump and Wayne/Batman aren't so different:
1. Both men were born in Gotham during the World War II era. (Wayne debuted in 1939; Trump in 1946.)
2. They both have been fond of the distinguishing article in their singular nickname (be it "The Bat-Man" or "The Donald").
3. One is a 6-foot-2 American billionaire who likes to emblazon a civic phallic symbol with his name. The other is, well, a 6-foot-2 American billionaire who likes to emblazon pretty much anything big with his name.
4. They both have self-named structures in Midtown (be it Wayne Tower or Trump Tower) over 50 stories high, from which they can survey their city.
5. Each is forever on the lookout for a large spotlight.
6. Their highly intelligent fathers profoundly influenced what career each son chose.
7. Each man has Scottish ties. (Trump on his mother's side; Batman co-creator Bill Finger has said that Bruce Wayne was partly named for Scotland's Robert Bruce.)
8. Each man is rather fond of having an apprentice or young sidekick to mold and scold, to banter with and correct.
9. Each man has appeared in a narrative alongside a younger female born Holly Robinson.
10. Each has an uneasy relationship with what he views as an "alien" presence, be the immigrant from Mexico or Krypton.
11. Each is eminently fond of private, sometimes custom helicopters, boats and planes.
12. Forbes has valued the fortune of each man at more than $4-billion. (In the case of Bruce Wayne: roughly $7-billion).
13. Both men have ties to people whose residence has been positively filled with cats (be it Selina Kyle or Chuck Blazer).
14. Batman and Trump have both had network series, for which they have received Emmy nominations. And each has also appeared as an animated character.
15. And contrary to the perception of some, neither man actually possesses a single superpower.