Will studying global business strategy help me if I am looking to create my own startup company?
Absolutely. Because even though you may start a company initially at the local level, you can go through SBA (Small Business Administration) to help you in setting up a local company with the county, state laws where you are. However if you start growing the company in leaps and bounds then your study on global business strategy will definitely help you in growing that business as will be able to ask intelligent questions with the authorities.
I think it's useful to take an international business class even if you intend to keep your startup local. As many perspectives as you can possibly get on business strategy and innovation will help you to make the best possible decisions for your business.