What did they think 12 years ago when Iran was part of the Axis of Evil? If trust takes a long time to build, there shouldn't have been any generated here.
Can you include specific examples of how popular EU opinion has driven policy? Typically the foreign policy of nations depends less on popular opinion than on geopolitical concerns. Your argument might be stronger if it focused on Trump's isolationist military and trade rhetoric, which both pose a much more significant threat to the current order in Europe and are a more substantial break from past USA policy than its attitude towards Iran.
Can you include specific examples of how popular EU opinion has driven policy? Typically the foreign policy of nations depends less on popular opinion than on geopolitical concerns. Your argument might be stronger if it focused on Trump's isolationist military and trade rhetoric, which both pose a much more significant threat to the current order in Europe and are a more substantial break from past USA policy than its attitude towards Iran.