Travel by water was quicker and better for long distance. However boats need to be built and are bulky. Travel by land is stealthier. Both have safety risks. Storms and jagged rock play a risk in water transportation. Land transportation can also be more exhausting, and more suspect to pillaging.
The answer is "amend". Think of the amendments ^^
If you are talking about them trying to expand in to present-day Canada, then it brought renewed conflict with Britain (war of 1812)
if it is towards the west, i guess it hampered technological development, because most people were moving west through the trails, instead of staying to help build up the economy
hope this helps
