"Winningmanship" is the the term for winning an argument, heated discussion or debate, or general disagreement.
To claim "Winingmanship", one has to declare "I win", "I am the winner" or even maybe "I have won" and that is the end of said conversation. That person has won, but is not necessarily right.
A: The Cheese People will take over Cracker Town for the sheer fact that they the ultimate weapon.....
K: But the Cracker race are superior to the Cheese People. Your ultimate is but a toy to us ha ha ha
A: I win.
A has claimed "Winningmanship".