When war breaks out, micro issues have a way of quickly becoming macro issues. Specific blockages and bottlenecks tend to cause broad supply disruptions and price pressure.And so it is with the war in Iran.Why it matters: Global supply chains have already been facing years of stress, first from the COVID-19 pandemic and then from the rise of tariffs and other trade barriers. The Middle East conflagration adds a new layer of stress.The good news for American consumers is that the biggest effects...