I think BRICS Nations want to undermine the US dollar as a reserve currency.This is potentially true. It might also push up production costs in other countries to the point where they have to raise prices. It might also inspire them to avoid the US market entirely and sell to BRIC countries, developing trade with other markets. This is already happening with the soy market.
What they should do is band together and resist. If they don't that'll give Trump the power to jerk anyone's chain at any time and get results.
Either way, its going to be a long miserable haul for everyone, include the US consumer.