Depends on the law and the State
But for California. It’s a coin flip on whether anything is illegal or not
Take a coin and flip it up in the air. Did it come down? it’s a crime
.
If it floats in the air, it’s still a crime


All silliness aside, I’m pretty sure,
"*Yes, California has a law against terrorist threats, which is now known as the Criminal Threats law:"*
“California Penal Code Section 422
This law makes it illegal to threaten someone with violence or harm, even if the threat is not intended to be carried out.”
That’s at State level, there is also a Federal Nexus for
In the United States, making a terroristic threat is a federal crime that can be charged as a class C felony:
“18 U.S.C. § 2332b(c)(1)(g)
This law makes it a felony to threaten to commit a crime that could result in death or serious bodily harm. The threat must be intentional, unequivocal, and specific, and must cause a reasonable fear in the victim.”
“25 CFR § 11.402
This law makes it a misdemeanor to threaten to commit a violent crime with the intent to terrorize someone, cause an evacuation, or cause serious public inconvenience”.
I’m not going to argue how many Angels can dance on the head of a pin or what the definition of the word is, is. I’ve seen case Where informing someone you have a gun has been charged as a “terroristic threat.” At both the State and Federal level.