You certainly would. I had very good results on clients' sites using a combination of varnish, cdn for images, and firewall to block any external probing - basi

You certainly would. I had very good results on clients' sites using a combination of varnish, cdn for images, and firewall to block any external probing - basically allowing only clean url GET requests to predefined set of urls, and blocking admin area access to anyone except whitelisted IPs. It's just as fast as a static site would be, and almost as secure. It takes more maintenance and costs a lot more to setup, but you get the benefits of CMS that all content authors/editors know how to use, so clients didn't mind it.