It is, assuming a permanent and guaranteed peace. But in the event some of those countries our supply chains traverse decide to alter the deal, it could mean we

It is, assuming a permanent and guaranteed peace. But in the event some of those countries our supply chains traverse decide to alter the deal, it could mean we suffer greatly since we depend on others so heavily - and eventually we might find we cannot make anything nontrivial domestically, as everyone who remembers how is dead. Defense is the most obvious area where you don’t want to be dependent on a country that might decide become an enemy for your military hardware, but maintaining more than just a defense manufacturing industry strengthens the country further.