@His4Life - I'm black too and I have to say while there is some truth in what you said the US was hardly built by black people alone. Aside from indentured European servants contributing to the building of this nation (as someone else pointed out earlier, though I'd add they weren't the main backbone of agricultural labor), Native Americans, Hispanics and Asians also contributed to the nation. Many of the nation's highways and rails were built by Mexican and Asian laborers. A lot of the country's major cities and high-rises were built by Native American, black and Hispanic laborers.
There was a time the country was built primarily on particularly black labor but that came to an end around the 1870s-1880s. Since then the nation's backbone for labor has been more multiracial though minorities still were disproportionately exploited for hard labor (like sharecropping, prison labor and minority scab workers and minority workers used in the New Deal works programs).