Answer:
The U.S. Constitution strengthened citizen's rights with the Bill of Rights, which is a series of constitutional protections against government power.
It strengthened national security by giving powers to the central power to coordinate defense matters: the president is the chief in command of the U.S. military, and the U.S. Congress is authorized to issue defense spending, and to declare war.
Finally, the constitution strengthened the economy by promoting a market system that promotes and protects property rights, which incentivizes people to consume, save, and spend, making the economy more dynamic.