Other countries should able to give a fuck to Trump.
Trump is acting like a tantrum toddler who always reach whenever other people making move, more and more US will lost their power because China is leading in economy. Trump has nothing to fight against BRICS except throw a tantrum by threatening to increase tariffs on other countries.
I don't think other countries care about that, especially since the BRICS countries have a large global population and economy, and they have sufficient resources without relying on Western Europe, so I don't think his threats will work.
Trump is essentially bluffing. If he loses, the country will lose its power. If there's even a little resistance, that resistance will be respected. However, high US import tariffs will impact its own people, making it increasingly expensive for goods to enter the US. In a way, this is true, especially what the BRICS are doing. In fact, it's a subtle way for the world to boycott America. If America does that, other countries will do the same. The trade war with China is already lost, let alone against a BRICS member. Perhaps it's time for US dominance to crumble; we're just waiting for it to happen.