Yes. If you are going on a cruise from a state side port, cruise insurance will work.
If you are traveling to another country, keep in mind that you are completely out of net-work, unless you have some kind of Elite insurance. There are some foreign countries that require thousands of dollars to see you, even in an emergency, and even with your elite insurance.
Your credit card insurance may cover some items but 3rd party travel insurance will cover a major "accident" and a minor incidental. You need to review the policy, as I am a Travel Consultant and not a Insurance agent. I would personally, not go to another country without being fully covered by Travel insurance. My health insurance will not cover me.