I would not think so. The passage will not allow such a rendering:
Rev 6:1, 2:
Then I saw when the Lamb broke one of the seven seals, and I heard one of the four living creatures saying as with a voice of thunder, Come.
2 I looked, and behold, a white horse, and he who sat on it had a bow; and a crown was given to him, and he went out conquering and to conquer.
Think about that. One doesn't conquer with a rainbow! Furthermore God's promise to Noah is "a sign" that He would not again destroy the earth by water. That is all rainbow is to us, a symbol of that promise.
One conquers with weapons, not rainbows. Paul tells us in 2 Corinthians 10:3-6
3 For though we walk in the flesh, we do not war according to the flesh,
4 for the weapons of our warfare are not of the flesh, but divinely powerful for the destruction of fortresses.
5 We are destroying speculations and every lofty thing raised up against the knowledge of God, and we are taking every thought captive to the obedience of Christ,
6 and we are ready to punish all disobedience, whenever your obedience is complete.
This "rider on the white horse" is said to go forth "conquering and to conquer", and he does it by the power of the gospel!
Compare him to the other riders:
Rev 6:3, 4:
3 When He broke the second seal, I heard the second living creature saying, Come.
4 And another, a red horse, went out; and to him who sat on it, it was granted to take peace from the earth, and that men would slay one another; and a great sword was given to him.
This rider has a distinct mission...to "take peace from the earth".
Rev 6:5, 6
5 When He broke the third seal, I heard the third living creature saying, Come. I looked, and behold, a black horse; and he who sat on it had a pair of scales in his hand.
6 And I heard something like a voice in the center of the four living creatures saying, A quart of wheat for a denarius, and three quarts of barley for a denarius; and do not damage the oil and the wine.
This black horse rider has the power over wheat and oil. In my view that is the antichrist because he has power over the basic needs of people. People had the need for food and oil (the oil for lamps). This represents (in my view) control over the food and oil in that day).
Rev 6; 7, 8:
7 When the Lamb broke the fourth seal, I heard the voice of the fourth living creature saying, Come.
8 I looked, and behold, an ashen horse; and he who sat on it had the name Death; and Hades was following with him. Authority was given to them over a fourth of the earth, to kill with sword and with famine and with pestilence and by the wild beasts of the earth.
This is Satan in my view. Jesus said "the thief comes only to steal, kill and destroy". Satan does that. he was cast down to the earth in Rev 12:7-9. This is how Satan has manipulated throughout time. Through war (physicaly and spiritually), which brings death!
The "white horse rider"is the ONLY rider where John doesn't expand on what his mission is after the breaking of it's seal.
When you do a word study on conquer, it allows these meanings:
1) to conquer
a) to carry off the victory, come off victorious
1) of Christ, victorious over all His foes
2) of Christians, that hold fast their faith even unto death against the power of their foes, and temptations and persecutions
3) when one is arraigned or goes to law, to win the case, maintain one's cause
Many look at these seals as judgment...but that is not what they are. These seals represent conditions on the earth.
*The gospel is going out through the church.
*War is a continuous reality.
*The necessities of life (food,oil..etc) gives nations power economically
I think the fact that John doesn't expand on the "white horse rider", says we need to consider what "white" represents. White represents purity of thought, mind, and purpose.
That is why I believe the "white horse" is representative of the "gospel of Christ" through which believers overwhelmingly conquer. I believe it is the Church conquering by the power of the gospel!
These seals also flow neatly with what Christ said to the disciples in the Olivet Discourse.
Make the comparison,,,