Two ways to convince your allies that you've won an argument on the internet
They both fall under "declare victory and go home." You may either claim your opponent's response was a non-response, or you may use the internet's most abused term and declare it a straw man. The problem is that too often, and perhaps most of the time, your worldview defines what you think is a strawman or a non-response.
Okay, the real problem is that you're arguing on the internet.