Those examples you gave are conditional and in some cases they were fulfilled. The civil war happened and there was mayhem. The United States army was defeated by the Mormons — see the Utah War or Buchanan’s blunder etc.
Anyway, by your standards, there are plenty instances of prophecies in the Old Testament and the New Testament not being fulfilled.
David W. Patten to go on a mission.
Verily, thus saith the Lord: It is wisdom in my servant David W. Patten, that he settle up all his business as soon as he possibly can, and make a disposition of his merchandise, that he may perform a mission unto me next spring, in company with others, even twelve including himself, to testify of my name and bear glad tidings unto the world. (Doctrine & Covenants 114:1)
This prophecy was made on April 17, 1838. David W. Patten died in October of 1838 and thus never went on a mission the following spring.
He didn't go on the mission. He died. This is a false prophecy. Nothing conditional about it. The "Lord" said he was to sell all his merchandise and go on a mission in the spring.
Another false prophesy commonly pointed to: The United States Government was to be overthrown in a few years.
I prophecy in the name of the Lord God of Israel, unless the United States redress the wrongs committed upon the Saints in the state of Missouri and punish the crimes committed by her officers that in a few years the government will be utterly overthrown and wasted, and there will not be so much as a potsherd left for their wickedness in permitting the murder of men, women and children, and the wholesale plunder and extermination of thousands of her citizens to go unpunished (History of the Church, Vol. 5, page 394).
Joseph Smith made this prophecy in May 6, 1843. However, the United States Government did not redress any of the wrongs committed against the Mormons in Missouri, and now over 150 years later, the U.S. Government still stands.
You say that almost 20 years later there was a civil war in the US. But the prophecy was the U.S. government would be "utterly overthrown" and that not so much as a "potsherd" would be left. Plenty of Civil War era pots still being sold at antique stores today, in the USA, a country not "utterly overthrown." False prophecy.