Conspiration is 30 years maximum. Actually committing a terrorist act and being convicted locks you up for good in a supermax prison. So yeah either way you're locked up for a VERY long time :/
People convicted for Jan 6 Capitol attacks are looking at 18 years[1] at least
18 years is by far the longest sentence handed down from Jan 6. Most convictions have resulted in probation. The Federal max sentence is rarely actually handed down. Typically, it’s closer to half the max with even that sentence shortened later on.
In the US? Absolutely. There was a very famous someone who just finished up a life sentence, and a quick google turns up https://www.fbi.gov/stats-services/publications/terrorism-20... which has, among others, 40 years for Matthew Hale, 39 years for Sean Michael Gillespie, and life for Ali Al-Timmi and Eric Rudolph.
People convicted for Jan 6 Capitol attacks are looking at 18 years[1] at least
[1]: https://www.pbs.org/newshour/politics/oath-keepers-founder-s...