Well, carry on and load it, it's your server.

Oh, wait, you mean you want ME to load it, into MY browser? That's a problem - my browser only loads JS from the origin server, and only if I give it explicit permission.

As a developer, I deplore the use of CDNs to serve javascript libraries; you don't know what the CDN is going to serve to your users, it could change without warning and break your site.