Can the Europeans Defend Themselves?

The NYT Room for debate (lacking Negroes as usual) asks the question "Can the Europeans Defend Themselves?"

The obvious question to anyone outside of Europe is "defend itself from who?" Who exactly outside Europe is threatening Europe? Is Libya threatening Europe or the other way around? What country outside of Europe is a military threat to Europe and actually is looking to exercise that military threat? China? Oh yes China is on the up, but China has a right to be on the up, after all it was Europe that invaded China and took Hong Kong. What do you think that "Great Wall" was built for? The Chinese were quite content to leave Europe alone. Today the US has warships in the pacific essentially flexing military might so far away from it's actual borders as to be on other people's border. So I'll ask again: Defend itself from who?