Well, I believe that the purpose of military is to protect your country and if your country do not have enemies than there no need to be a part of arms race.
BTW, can you explain why saudi arabia deserve to be conquered?
You are still missing the point so let me try again...
If I stake out a piece of land in the wilderness somewhere, the
FIRST thing I would do with myself and my weapons is to defend what I claim, not to seek out someone else's claim to take, and regardless of whether I have enemies or not because I do not know if the other guy over the hill is satisfied with his piece of land or not and may want mine.
The issue here is attitude: If you have done all you can with your country's wealth, from the human capital to the natural resources, from allocating for defense, education, trade, etc...And you are conquered by a superior foe, you would earn sympathy from all corners. But if you do nothing or very little and got conquered, in principle, other countries would condemn the conqueror but behind closed doors, they would privately criticize you for what you know is necessary but did nothing about it. As I ages, I balance out my idealism with pragmatism. In principle, if a woman walks nude down the bad street and got assaulted, I would definitely condemn the guilty to the fullest, but behind closed doors, the woman would receive far less sympathy from me than what she would expect. That is human nature.
I do not believe that Saudi Arabia deserve to be conquered out of the blue but if the kingdom does nothing to the best of its ability to defend itself by way of saying so-and-so is just a waste of money because some day there will be a counter to so-and-so weapon system, then
IF Saudi Arabia is conquered by a superior foe thanks to that careless attitude, there would be no sympathy to counter my condemnation of the conqueror. I make no apologies for my country's defense spending. I believe we are doing it just right.