Maybe you should also explain that to American journalists? Absolutely nobody on the left seems to be even remotely consistent with that statement.
If somebody thinks voting for Trump was wrong, he emphasizes that white people voted for Trump. We don't look at or care about if more Italian-Americans, German-Americans, or Swedish-Americans, voted for Trump, it's simply white people. Nobody even started an attempt to find the answer because nobody cares.
After the Vegas shooting, 'white people and mass shootings' has become a meme in the MSM (even though perpetrators of all ethnicities are close to their % of the American population btw), nobody tries to find out whether Americans of Italian descent or Americans of British descent commit more mass shootings.
When the media talks about behavior which they think is linked to a certain group, this group is 'white people', not Southern-, Central- or Northern- Europeans.
When social scientists conduct surveys, you'll find a distinction like X% of black people think..., Y% of white people think.....
I've never seen a study, at least not recently, which looks at 'X% of Americans born in families of Italian descent think..."
Looks like white people, a white race or white culture only exists when we try to assign some sort of problem to a group of people.