As you posted yourself, the 10 horns are 10 nations. The little horn is a nation also, plucking up 3 other nations by their roots.
My outlook is that America is the little horn. When we started as a nation, we were small, a sprout, a twig. We displaced Britain, Spain, and France on this continent.
The bible says that the little horn comes out of ROME.
Where does the Bible say that?