All have been good points to consider. Yet I am still not convinced that it is commanded to never fight back. The Old Testament is full of God instructing the Jewish tribes to fight back against their attackers. And if turning the other cheek was intended to be the only response that a Christian should engage in then explain why Jesus did not do that when he ran the money changers /lenders out of the Temple. Instead he took direct , physical aggressive actions against them.
I do not think it is as cut and dry as some are presenting it to be.
As far as Jesus stopping the use of swords to save him from his known and purposeful fate that is easily understood. He was giving his life for all of us and did not want that sacrifice stopped..-Tyr
18 U.S. Code § 2381-Treason Whoever, owing allegiance to the United States, levies war against them or adheres to their enemies, giving them aid and comfort within the United States or elsewhere, is guilty of treason and shall suffer death, or shall be imprisoned not less than five years and fined under this title but not less than $10,000; and shall be incapable of holding any office under the United States.