Jehal - I already said the UK has been America's greatest ally for many decades.
Europe has a great deal to be grateful to the USA for but don't pretend the USA (eventually) entered WWI and WWII for anything other than reasons of self-interest (Lusitania; Pearl Harbor)
There is no comparison between those events and the crisis that will now be triggered by President Trump's actions. Sometimes your best friend needs to tell you when you are making a mistake.