paul, the exclusivist

From Mike Wittmer:

I want to throw out a passage which seems to imply that Paul assumed that exclusivism was true. I would be interested in learning how an inclusivist would read this passage, so if that is your view, feel free to jump in.

In 1 Thessalonians 2:15-16 Paul writes that the Jews “displease God and are hostile to all men in their effort to keep us from speaking to the Gentiles so that they may be saved.”

Paul seems to assume that the Gentiles will not be saved unless he speaks the gospel to them (this coheres with what he explicitly says in Romans 10:13-15). If you had asked Paul, but can’t the Gentiles be saved in some other way, perhaps by responding to the general revelation of God in nature, is it likely that he would have said yes? (see Romans 1:18-23). Given these passages and his missionary activity, what are the odds that Paul was an inclusivist?