Three reasons:
1. Communicate the economic success of legislation he signed into law: From touting a solar energy manufacturing deal in the state to also an opportunity to promote the $11 billion private companies have invested in South Carolina manufacturing and clean energy since he took office as well as $2.6 billion in federal money awarded for the state's infrastructure projects. Biden wants to stay on message that Bidenomics is working.
2. Manufacturing in the Southeast of the United States is powering the country forward with jobs and opportunity: US manufacturing is experiencing a rebound, with companies adding workers amid high consumer demand for products, namely in the Southeast states of Georgia, North Carolina, and South Carolina. Plus, with Georgia and North Carolina being Electoral College battlegrounds, it is smart politics for Biden to spend as much time in the region before November 2024 as possible.
3. Contrasting economic message with the GOP presidential candidates: South Carolina is the home to two GOP candidates, Nikki Haley and Tim Scott, and the state's GOP presidential primary will go a long way in deciding who the GOP candidate will be in November 2024. So it's a good "Always Be Communicating" tactic to get into the state and mix it up on the campaign trail.