system
Given the following post, respond as if you're commenting on Reddit:
human
[Frozen] Is there some effective check to Queen Elsa's powers that other nations can put into use if necessary?

I represent a think-tank approached by several nations concerned over the abilities of Queen Elsa of Arendelle. After observing her magical control over the elemental forces of cold itself, many sovereign states are fearful of her using this power offensively against them and not having an effective way to fight back. We are aware that she claims benevolence and wants peace with her neighbouring countries, however it would be irresponsible to not have some contingency in place in case she goes rogue or becomes involved in a war. The crisis of the events of her coronation dramatically underscore the necessity of such planing. Her first act as queen involved an emotional outbursts that preternaturally froze her kingdom in a magically induced winter, and would have condemned her citizens to starvation or fleeing as refugees. Fortunately she reversed the effects before it was too late, but many question her capacity to rule, as it seemingly appears she did not receive proper diplomatic and political training by her parents.

What methods can we put in place to ensure our ability to fight back should a war erupt between our nations? How can we effectively check or remover her powers should the need arise?
gpt
Elsa's functionally an ice goddess, but that goddess lives in a body made out of the same meat as the rest of us. There's no indication that poison or a sharp knife won't get the job, if properly used. 

Maintain full diplomatic relations with Arendelle, and keep someone on the staff who has a background in such work. Someone with a posting that will get them in the palace on a regular basis, so they can get a feel for the staff, procedures and security. Some matter of trade representative, or a military/cultural attache would justify their presence, without burdening them with too many fake duties. In event of war, have them slip in and sort things out. 

As far as removing her powers, dispatch agents to the northern areas of Arendelle on the pretense of making deals with the local ice cutters, and seek contact with the trolls. They are pretty much the experts in the field.