The article says he was charged with obstruction.
You can try this "gift link" to the article: https://www.nytimes.com/2026/08/21/us/politics/samuel-tunick...
The gift link shows only a fraction of the article text. Just stick to https://archive.is/SflVC.
He is charged with obstruction, but under domestic terrorism (as defined by a national security presidential memorandum).