If a man needs something for the good of others and the other refuses to listen even after the threat of violence then I believe violence is necessary to achieve the thing which is beneficial for others.
Violence makes people distorted. If I want ham for my dying family and a rich man won't give it it seems simpliest to show him a basic human emotion, love and express that people are the same to him then to hit him and give in to his ignorance a or cruelties. All humans are the same, we all have the same nature if not deviated. All men experience the same emotions, white, black, muslim,Jew we all have the same organs and we will all die if poisoned or laugh if tickled. To make connections is easier and leads to happiness more than further corrupting, disabling or scaring a person.
That is not the question at hand though, we are not debating whether or not you should use reason or violence to solve a problem, the question is if you should use violence if reason fails. If not violence what else should you do if reason fails, violence is the best and most reasonable option.
By saying best method, you consider whether it is just, and humane.
Understanding is more easily accessed. People can condition themselves to not be affected by violence. But emotions are present in all.
I'm saying that compared to the other options if there are any, out of them violence is the best option. Understanding on the other hand is not even an option since the question states that men won't understand.
I simply thought that emotion, and understanding them was a part of reasoning with them. To reason with someone you have to understand what kind of situation they are in and you have to connect with them on an emotional level. When you do this you then begin to reason with them. If this does not work then violence is the next logical answer.