I think it's not about the truth in that message, but rather how the message is delivered, and how the kernel of truth is planted into what context.
For example, the same message could be told by referring to respect instead of fear.
"I want less war. You only stop war by having the best technology so much that earns the respect of your adversaries. If they don't respect you, if they don’t respect the might that your army can summon, you. Instead of going along with you, they will attack you at the next opportunity"
The issue is that by introducing hyperbole, the meaning changes completely. Take the two statements:
1. I want peace.
2. a) Therefore I need to be strong enough to deter any attack.
2. b) Therefore I need to be so strong that all my enemies fear me.
2. a) is sound. Nobody attacks if they believe the cost is higher than benefit. ("Believe" is doing heavy lifting here, most wars start when countries belief about cost/value is misaligned)
2. b) is incompatible with 1. Either you believe that a stronger party does not necessarily attack weaker parties, thus peace could also be maintained without supremacy, or you believe supremacy leads to wars, but then your own goal of supremacy cannot be in the name of peace.
Unless, of course, you're a race supremacist, who believes you're so much wiser and more moral than anyone else that only you can be trusted with unchecked power. An idiotic and immoral position to take.
Wrong. 2b is compatible with 1. You can have peace without military supremacy, for a time at least. But you can guarantee peace with military supremacy. That's the difference.
You are at your enemy's mercy without it. They may conquer you on a whim, and there's not a thing you can do about it.
I would much prefer that military supremacy in the hands of the wise and moral, there's nothing idiotic or immoral about that (indeed, the opposite is idiotic and arguably immoral).
Although I agree with you in principle, after having seen what Putin is doing in Ukraine, I believe the original message would reach the target better than yours.
To add to the confusion, you can have military intelligence assess your potential target and still fail miserably just like Putin failed in his blitzkrieg. So a little bit of saber-rattling might serve a purpose, I guess.
For example, the same message could be told by referring to respect instead of fear.
"I want less war. You only stop war by having the best technology so much that earns the respect of your adversaries. If they don't respect you, if they don’t respect the might that your army can summon, you. Instead of going along with you, they will attack you at the next opportunity"