Exporting cultural strictures rarely ends well (many historical examples, both distant and recent), so I'd say, if you can get a large number of people in the W

Exporting cultural strictures rarely ends well (many historical examples, both distant and recent), so I'd say, if you can get a large number of people in the West to not eat meat, then you've reduced the suffering of animals by a tremendous amount. That alone is a perfectly fine goal. Let non-coercive cultural influence do the rest of the work, while never forcing a populace to do something against its interests or will. (After all, non-Western vegetarian cultures have influenced Western diets...)