Tugs!, an interactive exhibition that will trace the past, present and future of the American tug, tow and barge industry, will open at Mystic Seaport Saturday, May 22. Designed for visitors of all ages, Tugs! will detail how tugboats play a crucial role in our 21st-century economy that is vital to American commerce and economic success. With more than 5,000 registered tugboats and towboats operating in the U.S., the industry moves more than 800 million tons of raw material and finished goods, including 60 percent of our nation’s grain exports and most of New England’s home heating oil and gasoline. Tugs! will present this powerful story through custom-created videos…