About NCMA. NCMA is the national trade association representing the producers and suppliers of concrete masonry products, including concrete block, manufactured stone veneer, segmental retaining walls and articulating concrete block. For over 100 years, the Associationâs mission remains to advance, protect and promote the common interests of its members.
Between 1803 and 1853, the United States almost tripled in size. In the early 1800s, the land west of the United States was very undeveloped.
Many Americans claimed that the United States had a manifest destiny to expand westward to the Pacific Ocean. U.S. attempts to purchase from Mexico the New Mexico and California territories failed. In 1846, after a clash of Mexican and U.S. troops along the Rio Grande, the United States declared war. American troops occupied the lightly populated territory of New Mexico, then supported a revolt of settlers in California.