How did the acquisitions of Oregon and Mexican cession relate to the idea of manifest destiny?

Both the Oregon and Mexican cession represent the Manifest Destiny idea of an America that stretches from coast to coast across the North American continent. The rhetoric employed in both cases exemplifies this further. The Oregon Cession was met with the phrase "54 40 or Fight!" which was a call against the British who were also vying for control of what's now British Columbia in Canada. The Mexican Cession was a byproduct of actual fighting following the Mexican-American war in the mid 1800s. In both cases, the acquisition of land was an American goal of controlling as much of North America as possible not only for economic purposes, but because many believed it to be their God-given right.