The correct answer to this open question is the following.
Although there are no options attached, we can say the following.
The effect of a lack of a navy have on American shipping was that it made the United States vulnerable against its enemies and had no ideal response in case of innovation. The lack of a proper navy did not allow the United States to support the transportation of goods and people in case of a conflict. It also made the US dependent on the navy of foreign countries such as Great Britain.
After the Revolutionary War, the US dropped the idea of having a formal navy. After 40 years without it, the end of the War of 1812 made politicians think about having some ships. From 1812 to 1860, the US navy was practically small compared to European superpowers.
