The most important facet of the foreign policy of the newly independent United States was primarily concerned with devising a policy to deal with the various Native American tribes it bordered. To this end, they largely continued the practises that had been adopted since colonial times by settlers and European governments. They realized that good relations with bordering tribes were important for political and trading reasons, but they also reserved the right to abandon these good relations to conquer and absorb the lands of their enemies and allies alike as the American frontier moved west. The United States continued the use of Native Americans as allies, including during the American Revolutionary War and the War of 1812. As relations with Britain and Spain normalized during the early 19th century, the need for such friendly relations ended. It was no longer necessary to "woo" the tribes to prevent the other powers from allying with them against the United States. Now, instead of a buffer against European powers, the tribes often became viewed as an obstacle in the expansion of the United States.