Final answer:
When a state constitution conflicts with the U.S Constitution, the U.S Constitution prevails due to the Supremacy Clause upheld by the Supreme Court. This has been enforced via a process called selective incorporation, where parts of the Bill of Rights are inserted into state laws. States sometimes try to block federal laws, but these attempts are often unsuccessful.
Step-by-step explanation:
When a provision in a state constitution conflicts with a provision in the U.S Constitution, the doctrine of Supremacy Clause comes into play. This principle, upheld by the Supreme Court, mandates that federal law, including the U.S Constitution, takes precedence over state laws and constitutions. Essentially, if a state law is found to conflict with the U.S Constitution, it can be deemed unconstitutional and therefore invalid.
In terms of historical context, the enforcement of this principle has been through a process called selective incorporation. Since 1897, the Supreme Court has continuously interpreted the U.S Constitution and applied it to varying times and circumstances. It selectively incorporates the Bill of Rights, effectively inserting parts of it into state laws and constitutions - even when a state constitution does not protect a liberty as fully as the Bill of Rights does.
However, there have been instances when states try to counteract this by attempting interposition or nullification to block federal government laws they view as exceeding the national government's constitutional powers. Despite such attempts, the federal law generally prevails, emphasizing the dominance of the U.S Constitution over state laws and constitutions.
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