link to original reddit post by /u/plazman30
Here is an article about it:
https://www.history.com/topics/united-states-constitution/mcculloch-v-maryland
From the article:
On March 6, 1819, the U.S. Supreme Court ruled in McCulloch v. Maryland that Congress had the authority to establish a federal bank, and that the financial institution could not be taxed by the states. But the decision carried a much larger significance, because it helped establish that the Constitution gave Congress powers that weren’t explicitly spelled out in the document.
That decision made it possible for the federal government to expand dramatically over the next two centuries, and to take on responsibilities that the nation’s founders couldn’t have envisioned. Without McCulloch v. Maryland, Congress wouldn’t have been able to create the New Deal or Social Security in the 1930s, or enact legislation such as the Civil Rights Act of 1964 and the Patient Protection and Affordable Care Act in 2010.