What does the end of Pax Americana mean for European security?

The end of Pax Americana signifies that the United States has effectively abdicated its leadership of the free world and will no longer serve as the security guarantor for Europe. This fundamental shift comes as America has made it clear it's stepping back from its traditional responsibilities in maintaining European security. As a result, European nations must now take greater responsibility for their own defense and forge a new collective security framework. General Sir Richard Shirreff emphasizes that this power vacuum requires Europe to strengthen its defense capabilities and spending to prevent vulnerability to potential Russian aggression and address the changing security landscape.