U.S. most likely will cease to exist long before antichrist takes power.
I don't where you get that I was referring to U.S. ?
The key in understanding the antichrist is that it was Lucifer's desire to imitate God in the heavenly realm that caused his downfall to Satan .
Satan's desire to be worshipped is no less today, and closing the book on the age, God will use him & allow Satan to finally get his wish to be worshiped for a short time here on earth to the detriment of those who have rejected His Son Jesus.
Satan will make full use of the short opportunity imitate God's actions on earth, performing miracles & even going so far as arranging a false resurrection of his son. the antichrist .
Rev 13:3
And I saw one of his heads as it were wounded to death; and his deadly wound was healed: and all the world wondered after the beast.
This one who appears to come back from the dead in imitation of Christ is the that Jesus spoke of :
Jhn 5:43
I am come in my Father's name, and ye receive me not: if another shall come in his own name, him ye will receive.