He didn't address it to the Jews; He addressed it to his spiritual brethren: the saved which are the spiritual Jews, but not because they were of the nation of Israel. Those with faith (see below), have been saved making them his spiritual brethren. Likewise, the twelve tribes represent spiritual Israel- the Israel of God- not the nation of Israel. They were "scattered abroad" because of their beliefs - they were spiritually persecuted as Christians. So, the book of James was addressed primarily to Christians.
[Jas 1:1 KJV]
1 James, a servant of God and of the Lord Jesus Christ, to the twelve tribes which are scattered abroad, greeting.
[Act 8:4 KJV]
4 Therefore they that were scattered abroad went every where preaching the word.
[Act 11:19 KJV]
19 Now they which were scattered abroad upon the persecution that arose about Stephen travelled as far as Phenice, and Cyprus, and Antioch, preaching the word to none but unto the Jews only.
[Act 11:21 KJV]
21 And the hand of the Lord was with them: and a great number believed, and turned unto the Lord.
[Jas 1:3 KJV]
3 Knowing [this], that the trying of your faith worketh patience.
[Jas 1:6 KJV]
6 But let him ask in faith, nothing wavering. For he that wavereth is like a wave of the sea driven with the wind and tossed.
Roger, looking back at your quote of verse one where he stated that it was addressed to the twelve tribes. Twelve tribes, I hope we can both agree, is Jews, not Gentiles. Spiritualizing the text to try and enlarge it to include those who could not possibly have been of the twelve tribes, that's very, very suspect, especially considering that he wrote his epistle before Paul had received revelation of the mystery and began to preach it on his first missionary journey.
James does not tie so easily into the language used in Acts to the extent that we cannot take thw words of James for what they say, so I'm therefore suspect of that tactic as well dare we become careless in drawing parallels that don't belong to each other in a comparative sense.
Additionally, James and the other apostles at that time were still preaching the Kingdom Gospel, which included works, faith, water baptism, repentance, and also observing that the Jews were still zealous for the Law. Paul's Gospel of Grace did not require works for justification, where the gospel preached by James did. I also don't buy the over-expansion of James' words by the tactic some have tried to employ in that Jesus completed the works for us. That would render the word of James silly at best, for he made no mention of Christ having fulfilled what he is instructing his Jewish audience to understand and practice.
If a Jehovah's Witness or Mormon tried to use similar tactics in support of their beliefs, you would call them out onto the carpet (or at least I would hope that you would call them out on that), so I hope you will appreciate my lack of so easily believing in these similar tactics whereby one injects concepts and meaning into a text that leaves no room for such in the way it is worded, such as a command, directive, instruction, etc.
MM