there's nothing more about it, it's all about strength. the entire world operates on the idea that the strong will destroy the weak, and they must therefore be strong themselves to prevent that from happening to them.

preventing Iran from getting a nuke is purely about preventing a potential rival from having the power to challenge them.

what exactly gives our government moral authority over the Iranians?

Arrogance.

I actually believe that any non-aligned nation needs a tactical nuclear program. Like, 1 Kiloton or half Kiloton warheads if they choose to be unaligned, but are surrounded by stronger powers.

Like, if Denmark and Switzerland want to remain neutral, but they are surrounded by France, Britain, and Germany who want to invade and take power, then Denmark and Switzerland need nukes to stop any real invasion by land, sea, or air. Yes, the bigger countries could use nukes, but why? At the end of it you get a million dead and irradiated neighbor that genuinely didn't want to be involved. It's kind of pointless if your point was to take the country with only a thousand dead.

For a smaller country, it would really be the only way to defeat a massive air-attack, naval task force, or armored rush.

How about not starting wars with allies...