Trump's move to block certain news outlets from White House access is drawing criticism even from supporters, and the worry is less about him than about who copies it next.

• The White House has shut specific outlets like CNN and Politico out of access, alongside a new $5,000 charge tied to press coverage.
• The charge itself is unpopular even among people who back the president on most things.
• The bigger problem is the precedent: once one president picks which outlets get in, the next one can do the same to the other side.
• Imagine a future Democratic president boxing out Fox using the same playbook — that is the risk being flagged.

Outlook: Expect legal and press-freedom pushback, and expect whoever holds the White House next to inherit the same power.