I think the point is that building world annihilating weapons is not an effective means to the achieving FTL tech. If we are still fighting wars and building weapons as the leading edge of scientific discovery and engineering, we are stuck in a literal dead end.

USA had nuclear bomb faster than USSR but USSR had nuclear energy plant before USA. And considering what's currently going in US and PRC space programs the latter is way more probable to reach it first.

Imo you'd need the entire planet to cooperate with itself in order to "move up the ladder" so to speak.