Everyone understands that without trade they would be dirt poor. If everyone had to be self-sufficient, they would be lucky to survive. It’s almost as obvious that the wider we can trade the more we can specialize in our comparative advantage raising the incomes of everyone. Where many stumble is at their national borders (though within national borders of large countries some regions restrict trade with other national regions to protect otherwise less efficient enterprises thus lowering incomes in general).
Why should trade be restricted across national borders? Three reasons stand out: two legitimate and one not. A potentially legitimate reason concerns national security. Requiring that products necessary for defense be domestically produced, even at greater cost, reduces the risk of supply chain disruptions. The risk is that this excuse is easily abused to the extent that such protection can turn illegitimate or corrupt.
A second legitimate reason also concerns resilience. The most efficient allocation of productive resources must take account of the risks of disruption to supply chains. We buy insurance for many assets and activities, thus incurring a certain cost, to protect our incomes from risks (large or small) of interruption and potentially larger losses. When buying goods or inputs from cheaper producers located far away, we are exposed to larger risks of supply interruptions. American manufacturers, for example, take these risks into account in deciding where to produce and purchase inputs to their products sold in the U.S.
A government bestowed financial favor on a firm or industry (trade protection, industrial policy) is always part of a quid pro quo. The firm delivers favors to the politicians who favor it. Government protection of otherwise uncompetitive firms increases their viability and profits but at the expense of lower income for the rest of us. Countries that heavily indulge in such protection have suffered lower levels of income. “Trade protection and corruption”
Following World War II, and the establishment of what became the World Trade Organization, barriers to trade (domestic protectionism) were gradually reduced via bilateral and multilateral trade agreements. In the 62 years from 1959 to2021, real United States’ per capita personal income, when measured in constant 2012 dollars to adjust for inflation, increased 297.1%, from $13,971 in 1959 to $55,477 in 2021. This huge increase is the result of increased productivity per worker. But such productivity gains are only possible because of trade (within or across national borders). “The case for trade”
Weaknesses in government programs to facilitate worker adjustments that are a necessary part of a dynamic, growing economy and other geopolitical factors are undermining the freest and most efficient trade (domestic and global) that our prosperity has depended on. “Geo Economic Fragmentation and the Future of Multilateralism” “End globalization?”
The Economist magazine has argued that: “One problem [with protectionism and industrial policies] is their extra economic costs. The Economist estimates that replicating the cumulative investments of firms in the global tech-hardware, green-energy and battery industries would cost $3.1trn-4.6trn (3.2-4.8% of global gdp). Reindustrialisation will raise prices, hurting the poor most. Duplicating green supply chains will make it costlier for America and the world to wean themselves off carbon. History suggests that vast amounts of public money could go to waste…. Yet rescuing the global order will require bolder American leadership that once again rejects the false promise of zero-sum thinking. ” “The destructive new logic that threatens globalisation”
Misinformation and corruption are undermining the basis of our incredible prosperity just when we need to pull together to deal with global warming. We must resist and fight back to restore and preserve our efficient market economies. They would not exist without trade.
Warren's space 
Warren, this is an interesting complex issues – global trading. However much has changed since you (and a bit less years, I) went to school. No doubt life has and will be richer for all (in many ways) if countries (even citizens) trade their products/services based on their experience and advantages (e. countries location, comparative advantages, citizens education, etc.).
However, stating “everyone understands that without trade they would be dirt poor”, is, of course, an exaggeration. Much depends on each country’s specifics and internal-external economies, population, etc. As you rightly point out, there are many complexities happening in the world, not least: wars, unfriendly political and military regimes, countries’ own interests and more. Therefore, your analysis is biased and light to take into account these new complexities we are living. Indeed, Globalization is, on paper, the way to maximize our living standards … but unfortunately that did not take into account the untrained citizens of every country. Even in the US (and the rest of the West), globalization did not address the issues of many citizens. Other countries in the West have weather these challenges better than the US due to their social safety nets, better education and adaptability. I would agree that we should not abandon trade. But it will have to be considered on an individual basis. I believe that many of the exported services, should be brought back to the home land and adapted to our local work force.
A second issue you may not be accurate is about “duplicating green supply chains will make it costlier for America and the world to wean themselves off carbon”. It’s not true. I would probably suggest a change of wording, more like ” Making supply chains cleaner will be an investment that will pay off in many ways including generating employment and supporting climate change mitigation and adaptation, and their co-benefits”. But you are not expert on the climate subject and even I (who have been thrown into this topics for 7 years) am not able to have solid statistics based on the climate science.
Thanks – as always, for a good read!