The Constitution still guarantees federal processes will take place in America, and means that the states have rights - because of the 10th amendment.
laws in states
States act as "labs of democracy," testing new policies and regulations that may be adopted nationwide.
Example: Abortion restrictions in some states have been upheld and replicated elsewhere.
States have significant control over lawmaking and citizens' actions.
Example: Cannabis is legal for recreational use in 24 states and Washington, DC.
Voting
Citizens get a degree of control over the policies of their states, which can tailor the policies of each state to the desires of its citizens.
At elections, ballot measures are put up for citizens to vote on, such as raising the minimum wage, and (before 2015) the legalisation of gay marriage.
Social policy
States still have high levels of control over social policy – for example, despite concerted efforts, there is still no standardised curriculum or assessment criteria for education.
State governments
All states have their own governments and constitutions which continue to operate independently from the federal government.