Even with the uncertainty surrounding Trump's future plans, it's doubtful that the travel ban will target non-Muslim majority countries. Trump has said repeatedly that he's in favor of legal immigration of best and brightest, and there's not a compelling point in his tweets, campaign promises, among his supporters, or in the GOP platform to exclude non-immigrant visitors from actual neighboring countries. It's not unreasonable to suppose that he understands that countries which possess a realistic geopolitical capability to retaliate (economically, mostly...) will make for tougher targets of travel restrictions, so neighbors Canada and Mexico would fall squarely in this category. Meanwhile, the currently affected 7 countries are easy targets: with the exception of Iran, they are experiencing struggles with internal governance and thus lack meaningful ways of resisting or retaliating against this unilateral move. Iran is included as an extra bonus, and its inclusion just resets US-Iran relations to pre-Obama days.

As for taking an ideological stance: weigh this choice yourself. It's doubtful that one person's protest will make an impact, but if you start or participate in a movement such that the social or economic impact is felt, you may have accomplished something. But don't count on it. Instead, investigate his previous tweets (luckily public info) and construct a profile of how you think he'll respond. I believe that Trump is not likely to be swayed by reason or protest, and is instead more prone to reactionary escalation.

But, as a resident alien (green card holder) from a boring, mostly-inconsequential European country, I won't be leaving the States just in case.