Maybe it depends on language, but I understand violance as to force or control someone, using authority, power, might, knowledge, aikido waza ... .
Violence just means do make someone do something against his own intention or will or wish. It is not about good or mal intent.
Brutality or bestiality is something different.
To do the same with a six year old child against it's will, is violence.
To make an inmate I work with calm down by bringing him to the ground an fixing him there until he relaxes is violence. But not mal intent.
Loving protection may use violence if needed. (Indeed exactly that is one of the reasons that made me start with aikido.)
I can do ikkyo or even nikyo without using pain. (On good days ...) And maybe you know that the aikido Endo teaches allways tries to use open hands, no gabbing, no muscle power, very gentle and open and "friendly". We are sometimes mocked as to "fondle uke to the ground".
But still this means to bring someone to the ground who wants to stay upright. And to guide someone on a way he doesn't want to go.
I make him ride on the same train I travel with. He doesn't ride on the train, leading to the destination he had in mind.
So this is kind of "kidnapping".
Maybe I sometimes felt a way of aikido you seem to describe. But it didn't convince me.
It didn't convince me, precisely because I didn't feel "dominated" by tori: I was allways free to do what I wanted to. To fall, to just go away, to punch tori into the face ... I had to be told how to behave as uke.
So I felt dominated not by tori, but by the teacher who told me what to do as uke, how to attack and when to fall. I had to restrain myself instead of being lead by tori. I didn't like that.
I don't think that aikido is different from other budo in this concern: For it is a budo, there is violance included. And on the other hand other budo also have ethics included like aikido has.
... well, I right walked into the trap ... had this discussion over and over ...
So what is force? It is violence. You may need to force a door open but if you do you are liable to cause some damage. Force by it's own nature is desrtuctive. So you can use it for many things, you can even harness it and direct it it to drive some kind of motor or something but then you come to the question of when is applied effort different to force.
Study takes effort, work is effort, effort is necessary in most all things. But force is different, and thus has an added quality of too much of something unnecessary. That something is violence.
Force violates. Aikido energy joins.
The inmate example you give is not one of you being violent as far as I can see. You see to understand what I am saying you need to understand basic human nature, true nature, not the meaning banded about. That inmate in truth didn't want to be violent and actually wanted someone to stop him being so and thus you acted in accordance with his true nature. He thus returned to a calm state. He could be himself again thanks to you. No damage done to him and your action prevented him doing damage to himself or others. Aikido in action.
Now if you could do the same thing without force, calmly and efficiently yet definitely then that would be pure Aikido. Or as I say Aikido.
All bullies for example underneath, in their hearts want to be stopped. They actually want to be helped. That's why when a person stands up to one they then want to be that persons friend.
Hitler with his armies wanted to dominate and bully etc. In response other countries stood up to him and much force was used and much violence and many lives lost. That situation is something that had been arrived at and ended up as war. Bottom of the scale situation. Many many situations prior to that had been gone through without being handled before it got to that final one.
These can all be looked at as examples of need for violence but it merely shows how ignorant we as human beings are to allow things to get to that point in the first place. We are not wise yet think we are and thus think violence is normal for use.
If on the other hand you studied the ways and means wars have been prevented you would find yourself studying such thins as diplomacy (real, not the usual wheeling and dealing) the art of peacemaking and thus the way of peace. If history books were filled with this history then people would be educated in a much better way of living and war would be seen in it's true colours. Stupidity.
The history of peacemaking far outstrips the history of wars by number and victory. Those who do not see this do not see what Ueshiba was saying either in my opinion. But then again how can many understand such enlightened views when they are not.
Can an unenlightened person understand fully an enlightened one? Thus it is a path and thus the first step is realizing that when such things as non-resistance and no enemies and no competition are spoken of they are real and it is up to us to find out how and why rather than translate it as yeah but it depends.