[landryraccoon]

Protectionist trade policy easily leads to wars. Banning goods produced with Chinese labor practices is tantamount to banning Chinese imports, which will have far reaching global implications beyond iPhones, and will increase military tensions greatly. Countries that don't trade find it much easier to start shooting at each other.

On the other hand, free trade leads to freer exchange of information, ideas, and aligns the incentives between nations so that cooperation is more beneficial. Powerful economic interests on both sides will have strong incentives to pursue peace. If those incentives are removed, nationalistic forces and firebrands have less of a counterweight to pursue miltaristic or aggressive policies.

As an example, think about the trade embargo against Iran. It was basically a declaration of war on Iran from the whole world. If the US institutes anything comparable with China it will be easily considered by China as an open act of hostility. This is how the Cold War 2.0 gets started.

[kobayashi]

You had me until your last para. The sanctions against Iran were most certainly not akin to a declaration of war. If Iran had viewed it as such, it would have likely closed the Strait of Hormuz in retaliation, which it regularly vows to do if a warring scenario were to arise. So not even Iran viewed the sanctions as war-like.

The sanctions were are digression from international norms meant to coerce an equally disruptive violation of international laws - the covert production of highly enriched uranium and the illegal development of nuclear weapons.

The implementation of trade restrictions on Chinese goods would probably start a trade war, and another Cold War seems to me to be a plausible outcome. I agree with your conclusion on that point.

[bmh_ca]

The relevant rules for trade wars are "national treatment" and "most favoured nation". You will see those terms quoted extensively in any legal trade dispute, notably before the WTO.

Labour laws per se do not violate mfn or nt, so long as the labour laws apply domestically as well as to imports (since trade wars are essentially about import tariffs).

The primary reason we do not apply labour law to the producers of imports is because labour is poorly organized, under funded, and lacks political will and/or forethought.