Well, the biggest issue would be in her getting caught - there'd be less issue if she did succeed. Yeah, a lot of people [i]would [/i]suspect the Gerudo even without any solid proof - but with the kind dead, it would be the queen's word that mattered at that point. If the king's forces openly disobeyed the queen/her regent aka the proper ruler in order to war with the Gerudo, welp, looks more like a civil war in the making.

For Nadi, any chaos Hyrule'd be plunged into after the king's death is a better scenario than the king going and "killing her people by the thousands."

Although to be fair, she hasn't really thought it that far. Her thoughts ended at "king wants to kill my people = fuck the king off with his head." She lived her entire life in the war, she doesn't have the most stable grip on this concept of "peace". |D''

But yeah, since she [i]would [/i] fail, [i]that [/i]would be prime fuel for another war, for sure. "Look, a Gerudo tried to murder the king!" But she hasn't exactly thought of the possibility of failure, so that's irrelevant to her thought process. To [i]her[/i], her plan makes sense.

Tl;dr: a real hothead she is, for sure.