The importance of Afghanistan can be seen from the fact that USA has not forgotten it. Very recently they did a drone attack killing Ayman al-Zawahiri and the air strike was done using air route that passes via Pakistan. USA has complete control over this region via Pakistan and Afghanistan until Taliban took complete control of Kabul.
The last Prime minister of Pakistan did show eyes to USA and other western countries and was quickly removed from power using Pakistan army. Afghanistan is important as it allow USA to sit on borders of China and keep a close eye on Russia also.
You have mentioned a very valid point here. There is so much protest around the world and in Pakistan too on the regime change, Pakistan Ex.PM openly says it in his interview - how dare USA send a cypher to remove the elected leadership from the power. Also he is not scared - going to public for the justice. And the whole nation stood by his side. Pakistan woke up and I wish the rest on the world too.