The Occasion of Romans

I've become convinced that the key problem with an Arminian is that he is confusing the occasion of writing Romans with the argument of it.
The occasion is Paul preparing to stop over and see them, so he writes a letter to them to let them know he and his missionary team intent to visit, and he would like their help. In the meantime he addresses the conflict of the Jews re-integrating into the church after they had been expelled by the city of Rome.
He writes on how righteousness is by faith alone, in Christ alone, apart from works. He dresses it up by pointing out when God planned this (in eternity past) who He's already done it on (Abraham, David) and why men need it.
Once you see that His real theme is righteousness it becomes evident that the problems between the two groups is settled by this same righteousness by faith. He's not showing why the Gentiles are in or out of a covenant family, he's showing imputed righteousness for all men.