The Defeat of the Kingdom of Satan.
Rev. 7:9-10   After these things I looked, and behold, a great multitude, which no one could count, from every nation and all tribes and peoples and tongues, standing before the throne and before the Lamb, clothed in white robes, and palm branches were in their hands;  [10] and they cry out with a loud voice, saying,   "Salvation to our God who sits on the throne, and to the Lamb."  (NAS)
Satan the father of lies has been defeated.  Even though he has had undiminished reign during the post-rapture period without restraint from the presence of the church – nevertheless there are to be a great multitude of the saved as the result of the evangelistic work of the 144,000 virgin Israeli males – from every tribe.  They will be led by the Lamb Himself and are to be the Firstfruits of the numberless of people who will be saved in the height of Satan's rule during the tribulation. Jesus Christ, the Lamb of God will personally lead these men in what will be the greatest world-wide evangelistic effort of all time.  Please read this passage from God's Word:
Rev. 7:11-14   And all the angels were standing around the throne and around the elders and the four living creatures; and they fell on their faces before the throne and worshiped God,  [12] saying,   "Amen, blessing and glory and wisdom and thanksgiving and honor and power and might, be to our God forever and ever. Amen."  [13] And one of the elders answered, saying to me, "These who are clothed in the white robes, who are they, and from where have they come?"  [14] And I said to him, "My lord, you know." And he said to me, "These are the ones who come out of the great tribulation, and they have washed their robes and made them white in the blood of the Lamb.  (NAS)
The Illustration of Battle Planning and its Victory.
The anti-christ will not escape the wrath of the Lamb of God for he also will be defeated.  Theodore H. Epp tells of the unholy trinity in his book Practical Studies in Revelation  Satan, the antichrist and the false prophet all are destined for an eternity in hell.  This victory is all accomplished by the Lamb because He was willing to shed His precious blood on the cross.  More than we can imagine was accomplished because of the role Jesus Christ accomplished as the Lamb of God and the Holy Spirit saw to it that John got that point in the Revelation Of Jesus Christ.
This whole subject of the Victory of the Lamb can be viewed from the military concept of strategic victory and tactical victory.  When a military campaign is set up by the generals there has to be a strategic plan – that is, there has to be objectives, contingencies, resources and a basic plan on how to win the victory.  When General H. Norman Schwarzkopf, Commander of Desert Storm presented the famous "Hail Mary" maneuver where our troupes were going to cut off the Iraqis from behind there were several strategic necessities.  First, there had to be the ability for speed over desert terrain. Then there had to be the night vision – then the supplies - resources and, of course, the plan had to be basically a sound one.  Then came the tactical execution of the strategic plan.  This is where the military personnel had to carry out the strategic plan.  The minute detail of this execution was the tactical plan – how many tanks – how many A10's how to take care of the land mines.  All this would have been for naught if the strategic plan was a bad one.  When the allies came up with the "Hail Mary" plan, it along with the night bombing of the Iraqis communication bunkers and many other parts of the overall plan, constituted a strategic victory – the plan was a winning plan.
Let's get back to God's plan of Redemption.  We were all hell-bound.  Simple as that.  Satan had us right where he wanted us – going to hell.  But God had a strategic plan – the Lamb of God dying on the cross.  Jesus' shed blood assured the strategic victory over Satan's plan of rebellion and the eternal damnation of mankind.
What about the tactical victory – if we can continue with this military campaign illustration – and I think we can.  Please turn to Matthew 16:17-19.
   And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven.  [18] And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.  [19] And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven.  (KJV).
"…and upon this rock I will build my church; and the gates of hell shall not prevail against it…." Make no mistake about it – this is Jesus' war against "Hell" itself – and I say "Hell" (with the caps) because He is talking about Satan not the lake of fire.  Jesus is characterizing Satan and his "world system" as "Hell."  Jesus is on the offensive against "Hell" (Satan's world system) and He is going to win.  Two interesting images come out of His phrase "gates of hell."  Let's take the images in reverse.  
"Hell" – the original for hell is hades.  In the classical Greek Hades was the god of the underworld and thus the place of his kingdom was so named.  In the LXX hades  is used in translating the word sheol.  Jesus used the Jewish concept of two compartments of sheol – one for the wicked and one for the righteous in the parable of the rich man and Lazerus.  The point I wish to make of this image of hell is that Satan's world is a place of desolation, of condemnation and death.  This is the kingdom that Jesus is making war on.  Satan's kingdom is condemned – it is nothing more than a system of the dying and condemned.
"As for you, you were dead in your transgressions and sins,  [2] in which you used to live when you followed the ways of this world and of the ruler of the kingdom of the air, the spirit who is now at work in those who are disobedient.  [3] All of us also lived among them at one time, gratifying the cravings of our sinful nature and following its desires and thoughts. Like the rest, we were by nature objects of wrath." Ephes. 2:1-3
Paul characterized Satan's world and it's citizens as objects of God's wrath.  It is a kingdom of the disobedient – of self-serving sinners but who were also captives of the power of the sovereign, Satan.  This is Jesus' military objective – the saving of sinners from Satan's kingdom and death – if I may use that description. 
Next, we have the image of the gates of hell.  The original is pule and refers to the fortified gates of a town that would be closed against the enemy should there be a seige.  It was also used in connection with the entrance to hell itself – the kingdom of god Hades in classical Greek.  So then, the complete picture that emerges is that Satan and his kingdom is under siege by Jesus Himself and the church is His army.  I have often said this – that it is not the church that is under siege by Satan – quite the opposite – Satan is under siege and he knows it.  That is not to say that he is powerless – ask any missionary in a dark pagan corner of the world or any one who is working a the crime – drug ridden neighborhood.  Satan is very much powerful and is not willing to give up any of his territory without a fight.  
The point I am making here is that you and I have read the last chapter: ,   "Amen, blessing and glory and wisdom and thanksgiving and honor and power and might, be to our God forever and ever. Amen." (Rev 7:12b) and again; "And I heard a loud voice saying in heaven, Now is come salvation, and strength, and the kingdom of our God, and the power of his Christ: for the accuser of our brethren is cast down, which accused them before our God day and night.  [11] And they overcame him by the blood of the Lamb, and by the word of their testimony; and they loved not their lives unto the death." (Rev. 12:10-11).  We have read the last chapter and we know that the strategic victory is won – that was won on the cross.  
We are now fighting the tactical battle and we are winning that one too.  On top of this, when the church is gone at the Rapture, even then, Satan will get no rest from the war of Jesus on his kingdom.  Israel will step in and the 144,000 evangelist from the 12 tribes of Israel will take up the battle.  Countless of people will receive Christ as Savior during the tribulation – they will have to give up their lives in service to Him and yet the millions from every corner of the earth will still keep on deciding for Christ!  The war is being fought now and it will not  be over until Jesus says it is – and that will be when Satan is totally vanquished and is spending an eternity in hell!
Listen to Theodore Epp in his book, Practical Studies in Revelation;  "The sentence of execution was given to Satan at the cross.  But the time of Satan's execution is future.  His judgment is certain and this is of comfort to the Christians.  The Apostle Paul assured the Christians at Rome that 'the God of peace shall bruise Satan under your feet shortly' (Rom. 16:20). First John 4:4 also reminds us of our victory through the Lord Jesus Christ: 'Ye are of God, little children, and have overcome them: because greater is he that is in you, than he that is in the world.' ' He that is in the world is none other than Satan himself.
Israel is victorious over Satan in Revelation 12.  But how is she victorious?  Verse 11 provides the key to not only how Israel will be victorious over Satan during the Tribulation, but also how we can be victorious over him today. 'They overcame him by the blood of the Lamb, and by the word of their testimony; and they loved not their lives unto the death.'"
Our Victory Song!
I have a video tape of an evangelist David Ring.  He has cerebral palsy but has overcome not only his resentment over past events in his life but God has called him into a ministry of winning souls for Christ.  At the end of this particular message "Why do Bad Things Happen to God's People"  he sings the song "Victory in Jesus" – absolutely a total disaster musically but is so moving that it leaves me in tears and thrilled to see what Christ can do in His battle to snatch sinners from the jaws of Hell.  The first verse is particularly meaningful in connection with this message:

Victory In Jesus.
I heard an old, old story, How a Savior came from glory,
How He gave His life on Calvary To save a wretch like me;
I heard about His groaning, Of his precious blood's atoning,
Then I repented of my sins And won the victory.

Oh victory in Jesus, My Savior, forever, 
He sought me and bought me With His redeeming blood;
He loved me ere I know Him And all my love is due Him,
He plunged me to victory, Beneath the cleansing flood.

The Kingdom of Christ, God's will Done on Earth.
It was the plan of the Father that man rule his domain on earth – that plan will finally come to it fulfillment in the God-Man Jesus Christ.  It will be a kingdom where righteousness the be the by-word in sovereign rule.  A look at Isaiah 11 would be helpful at this point;
And there shall come forth a rod out of the stem of Jesse, and a Branch shall grow out of his roots:  [2] And the spirit of the LORD shall rest upon him, the spirit of wisdom and understanding, the spirit of counsel and might, the spirit of knowledge and of the fear of the LORD;  [3] And shall make him of quick understanding in the fear of the LORD: and he shall not judge after the sight of his eyes, neither reprove after the hearing of his ears:  [4] But with righteousness shall he judge the poor, and reprove with equity for the meek of the earth: and he shall smite the earth with the rod of his mouth, and with the breath of his lips shall he slay the wicked.  [5] And righteousness shall be the girdle of his loins, and faithfulness the girdle of his reins. (Isaiah 11:1-5, read the rest of the chapter).
No more the wicked politics of today.  There the Lord will rule with absolute fairness and firmness.  Yes, there will be occasional rebellion during the millennial reign of Christ but Jesus Christ will rule with complete sovereignty as a righteous, fair ruler.
Jerusalem will be the capital during the Millennium; "And it shall come to pass in the last days, that the mountain of the LORD'S house shall be established in the top of the mountains, and shall be exalted above the hills; and all nations shall flow unto it.  [3] And many people shall go and say, Come ye, and let us go up to the mountain of the LORD, to the house of the God of Jacob; and he will teach us of his ways, and we will walk in his paths: for out of Zion shall go forth the law, and the word of the LORD from Jerusalem.  [4] And he shall judge among the nations, and shall rebuke many people: and they shall beat their swords into plowshares, and their spears into pruninghooks: nation shall not lift up sword against nation, neither shall they learn war any more." (Isaiah 2:2-4).  The world will see the rule of righteousness.  War will be a thing of the past.  Yes, there will be the reproof against the rebellious. But you and I brother and sister will finally be with Him forever.  The battle's won – we rest in Him forever – Amen!