I would like to see this question moved to the Social Sciences Discussion Forum with the hope that there are editors or readers out there who live in Texas and would add their responses to this quote!
The quote is saying that Texas is a reflection of the United States, only on a larger scale than would be expected to be the case for any one state. Physically, Texas is larger than all the states except Alaska. Texas's population is second only to New York, with a number of the nation's largest metropolitan areas within its borders. The economy of the one state is similar to the economy of the entire nation of Canada or India. The variety of landforms within the state's boundaries, the engagements with foreign powers through its history, the impact of its businesses, schools, and agricultural systems upon the rest of the nation - all could be seen as being enhanced as if the state were on steroids.