What is the biblical basis for a post-tribulation rapture? I am fairly well-versed in premillennial theology, however, I was challenged frequently while at Bible College on my point of view of a pre-tribulation rapture in favor of a post-tribulation rapture. I understand the principles of post-trib thought, but I fail to see any scriptural evidence for it. Can someone please point me to the scriptural evidence used to support a post-tribulation rapture?

I have read "Gospel of the Kingdom" by George Eldon Ladd and I enjoyed it, but I suppose that perhaps I did not properly understand it or his argument for a post-trib rapture.
Revelation 1:9


  I, John, both your brother and companion in the tribulation and
  kingdom and patience of Jesus Christ, was on the island that is called
  Patmos for the word of God and for the testimony of Jesus Christ.


The "great tribulation" is not a future event, it is an ongoing event. The Apostle John speaks of himself as enduring the tribulation of Jesus Christ during his lifetime. This tribulation will continue straight up until Jesus returns. His return marks the end of the tribulation, and the immediate beginning of eternity.

Many scriptures speak of the last trumpet, the seventh trumpet, or the great trumpet.

Matthew 24:31


  And He will send His angels with a great sound of a trumpet, and they
  will gather together His elect from the four winds, from one end of
  heaven to the other.


1 Corinthians 15:52 


  in a moment, in the twinkling of an eye, at the last trumpet. For the
  trumpet will sound, and the dead will be raised incorruptible, and we
  shall be changed.


1 Thessalonians 4:16 


  For the Lord Himself will descend from heaven with a shout, with the
  voice of an archangel, and with the trumpet of God. And the dead in
  Christ will rise first.


Revelation 11:15 


  Then the seventh angel sounded: And there were loud voices in heaven,
  saying, “The kingdoms of this world have become the kingdoms of our
  Lord and of His Christ, and He shall reign forever and ever!”


My understanding of these scriptures is that they all describe the same event:

The Lord comes, raises the dead, and gathers the elect to bring them immediately to heaven. This is an apantesis, when a delegation leaves a city to escort in a dignitary and escorts that dignitary into the city. Examples in scripture are:


King David greeting the Ark of the Covenant when it was brought into his city
Jesus being greeted on Palm Sunday and escorted into Jerusalem.
Paul the Apostle being escorted into Rome for his visit.


Thus Jesus is leaving the heavenly city with a delegation of angels to welcome in his Church, only to quickly return to that heavenly city. It will not be secret, and when it happens, all wars will cease. There will be no more tribulation after Christ's appearance.