1990-Subsec. (a). Pub. L. 101–649, §543(b)(2), inserted "or attempts to enter" after "(1) enters" and "attempts to enter or" after "or (3)", and substituted "shall, for the first commission of any such offense, be fined not more than $2,000 (or, if greater, the amount provided under title 18) or imprisoned not more than 6 months, or both, and, for a subsequent commission of any such offense, be fined under title 18, or imprisoned not more than 2 years" for "
shall, for the first commission of any such offenses, be guilty of a misdemeanor and upon conviction thereof be punished by imprisonment for not more than six months, or by a fine of not more than $500, or by both, and
for a subsequent commission of any such offenses shall be guilty of a felony and upon conviction thereof shall be punished by imprisonment for not more than two years, or by a fine of not more than $1,000".
So, yes, despite the blithering imbecilic shit you've been brainwashed to believe,
these are criminal offenses with attendant civil penalties.
They are
not civil offenses.