This suggests America is fundamentally the same country of concerned, good-hearted citizens it ever was.

it ever was 是定语从句，之前省略了关系代词 that，先行词是the same country。

of concerned, good-hearted citizens ， of 表示“组成”，等于：made up of concerned, good-hearted citizens 之意。

【翻译】这表明，美国从根本上来说还是一个由关心、善良公民组成的国家。