Okay, it may have been a misundersanding. It appeared to me you were implying that HIS appearance in the clouds was not a physical appearance, OR that HE is not physically appearing to those who look for him! That may have been a misunderstanding on my part, or poor choice of wording on your part, or a combination of both. IT LITERALLY WILL HAPPEN PHYSICALLY.
The difference between the SECOND COMING and the earlier RAPTURE; is easy to explain.
SECOND COMING, is obvious, it happens SO SLOWLY all the worlds Armies has time to move their Armies to ISRAEL to try to STOP HIM.
RAPTURE, is an event that HAPPENS SO QUICKLY, it is equated to lighten flashing across the Sky, and every eye the looks up will see it.
Matthew 24:27 (HCSB)
27 For as the lightning comes from the east and flashes as far as the west, so will be the coming of the Son of Man {for HIS Bride} .
Revelation 19:11-21 (HCSB)
11 Then I saw heaven opened, and there was a white horse. Its rider is called Faithful and True, and He judges and makes war in righteousness.
12 His eyes were like a fiery flame, and many crowns were on His head. He had a name written that no one knows except Himself.
13 He wore a robe stained with blood, and His name is the Word of God.
14 The armies that were in heaven followed Him on white horses, wearing pure white linen. {That is US, ref. Rev. 6:9-11.}
15 A sharp sword came from His mouth, so that He might strike the nations with it. He will shepherd them with an iron scepter. He will also trample the winepress of the fierce anger of God, the Almighty.
16 And He has a name written on His robe and on His thigh: KING OF KINGSAND LORD OF LORDS.
17 Then I saw an angel standing on the sun, and he cried out in a loud voice, saying to all the birds flying high overhead, “Come, gather together for the great supper of God,
18 so that you may eat the flesh of kings, the flesh of commanders, the flesh of mighty men, the flesh of horses and of their riders, and the flesh of everyone, both free and slave, small and great.”
19 Then I saw the beast, the kings of the earth, and their armies gathered together to wage war against the rider on the horse and against His army.
20 But the beast was taken prisoner, and along with him the false prophet, who had performed the signs in his presence. He deceived those who accepted the mark of the beast and those who worshiped his image with these signs. Both of them were thrown alive into the lake of fire that burns with sulfur.
21 The rest were killed with the sword that came from the mouth of the rider on the horse, and all the birds were filled with their flesh.
That is when HIS FEET touch the GROUND on the Mount of OLIVES, splitting it in two. It is not a COMING until HIS feet touch the GROUND.