The relationship between the national government and state governments is very important in the United States. This mix is called federalism, and it helps shape how the country is run. Here are some key ways the national government can influence what states do:

1. Grants-in-Aid

One main way the national government helps states is by giving them money. These financial gifts are known as grants. They encourage states to adopt certain policies. For example:

• Medicaid Expansion: The Affordable Care Act gave states money to expand Medicaid. States that accepted this funding could improve healthcare. However, those that didn’t get the funding missed out on a lot of money.

2. Conditional Grants

The national government can also set rules for how states can use the money they receive. These rules can guide state actions. For instance:

• Highway Funding and Speed Limits: In the 1970s, the national government required states to raise the legal drinking age to 21 in order to get federal money for highways. States followed this rule to secure the funding, showing how money can change state policies.

3. Federal Mandates

Sometimes, the national government can require states to follow certain laws, even without providing money. These are called unfunded mandates. A good example is:

• Americans with Disabilities Act (ADA): Created in 1990, this law requires states to make sure that people with disabilities have access to public spaces. States have to pay for these changes themselves, which can lead to big policy changes.

4. Preemption

According to a part of the Constitution called the Supremacy Clause, federal law can override state laws. This means that if there’s a conflict, federal law wins. For example:

• Environmental Regulation: The Clean Air Act lets the national government set standards for air quality. This can cancel out state laws that are less strict, making sure everyone follows the same rules nationwide.

5. Judicial Influence

The national government can also change state policies through court decisions. When federal courts decide on important issues, states may need to change their laws. For example:

• Same-Sex Marriage: In 2015, the Supreme Court ruled in a case called Obergefell v. Hodges that same-sex marriage is legal across the country. This decision made state laws against same-sex marriage invalid.

Conclusion

These examples show how the national government shapes state policies. States have the power to create and enforce laws, but they often have to deal with the influence of federal rules and priorities. The back-and-forth between state and national governments is a key part of American federalism, highlighting both teamwork and disagreement in making policies.