Was the Mexican War an Exercise in American Imperialism?

I personally agree with the "yes" article. We did wage a war on Mexico for greedy reasons. We wanted land, "Manifest Destiny."
My personal reasons may be getting in the way, but I thought that the "yes" article was better. It states key points. "Manifest Destiny," we wanted land, and Mexico was in our way. They were not selling us the land, so we decided to take it with force. When we took half of Mexico's land, Mexico never fully recovered, so was that really necessary. We seriously hurt another nation.