The WTS teaches that
1) There will be a call that "peace and security" has been acheived (1 Th 5:3)
*** w04 2/1 p. 21 par. 11 "The Scene of This World Is Changing" ***The apostle Paul foretold that just before this system of things is destroyed, there will be a notable expression of satanic propaganda. He wrote: "Whenever it is that they are saying: ‘Peace and security!’ then sudden destruction is to be instantly upon them just as the pang of distress upon a pregnant woman."—1 Thessalonians 5:3; Revelation 16:13.
2) The GT starts when elements of the UN will attack and destroy all religions except jws
*** w97 5/1 pp. 17-18 par. 17 No Peace for the False Messengers! ***Shortly, "crazed" members of the UN will be maneuvered by Jehovah to turn on false religion, as described at Revelation 17:16: "These will hate the harlot and will make her devastated and naked, and will eat up her fleshy parts and will completely burn her with fire." This will mark the start of the great tribulation that is referred to at Matthew 24:21 and that will climax at Armageddon, the war of the great day of God the Almighty.
3) Satan or Gog of Magog will attack jws with the view to destroying them
*** w07 8/15 p. 26 pars. 17-18 Jehovah Is a Lover of Justice ***Satan and his followers will soon come against Jehovah’s worshippers in an attempt to stamp them out. (Ezekiel 38:14-23) That will be part of what Jesus called the "great tribulation such as has not occurred since the world’s beginning until now, no, nor will occur again." (Matthew 24:21) Will Satan’s attack succeed? No. God’s Word assures us: "Jehovah is a lover of justice, and he will not leave his loyal ones. To time indefinite they will certainly be guarded; but as for the offspring of the wicked ones, they will indeed be cut off. The righteous themselves will possess the earth, and they will reside forever upon it."—Psalm 37:28, 29. The attack by Satan and his horde on Jehovah’s servants will be the final insult. Jehovah foretold through Zechariah: "He that is touching you is touching my eyeball." (Zechariah 2:8) It is as if someone were thrusting a finger in Jehovah’s eyeball. He will respond immediately and eliminate the perpetrators.
4) God will step in to protect jws which starts Armageddon where all non-jws on earth will be destroyed forever and Satan and his angels/demons will be abyssed for a 1,000 years.