wp_enqueue_script is rewriting my URIs

This is a really lean theme built using Underscores.me, so there is no weird extra code.

All I’m trying to do is use the Bootstrap CDN, but for some reason, it rewrites https://….com to my site URL, breaking the link.

This is my enqueue script:

wp_enqueue_script( 'bootstrap-js', 'https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js', array('jquery'), '', true );