Jabberwock, Beware!

The aliens offered Earth one chance for survival: beat them in an intellectual duel. So Joe Waters rose to the task, grim—and drunk!...
The Security Council was in emergency session. The four delegates would have had easier consciences had more nations been represented, but it was hard to travel now. Only Russia, England and France were able to send their men to New York.
Sergei Moskov, USSR, presided unofficially. He wore a harried look, and addressed them wearily.
To think, gentlemen, that it has taken circumstances like these to bring us into accord!
The others said nothing. Overhead, above New York's stone and glass UN building that had been conceived in hope and wrought with faith, they could hear the whine of the patrolling ships. The delegates stared at the table in front of them.
Your country, Mr. Conrad, Moskov said to the American representative, is the mother of our last hope. He looked around the table for concurrence. Sir Manly straightened a bit, and M. Tourneau's mustache twitched, but they all nodded. What use national pride now? There was not much time, anyway. Tonight....
He will be here? Moskov asked.
Conrad cleared his throat. He reached into his coat pocket and pulled out a slip of paper.
Joe—I mean, Dr. Waters—sent an answer to our request. He read:
'I take my vorpal sword in hand. Beware, Jabberwock—I come. Joe Waters.'
The courage of youth, Sir Manly said, but he smiled.
Moskov looked at his watch. He should be here, then.