I was detained for protesting Trump. Heres what the Secret Service asked me

[Lee-Lee]

32. There are many things

Trespassing comes to mind as one, if the venue has rules posted as to acceptable behaviors. If your physically attaching a sign to property that isn't yours that isn't allowed in almost any business. State and local laws can vary as to if a person must be personally warned before trespassing can charged in many cases- sometimes an in person warning on record is needed, sometimes just a sign that a person disregards.

Depending on the state and local laws any variation of laws on disorderly conduct, breaching the peace, etc. can be applied.

Yes, you First Amendment rights are limited on private property. You do not have a right to go into someone else's property and say anything you want without being told to leave. You can't go hang signs and banners on other people's property without permission. That's always been the case and always will be. And it's not a violation of your First Amendment rights because a property owner is free to set any rules that apply on their property that they want. It isn't the government restricting your speech, it is the property owner setting rules and the government only enforcing the laws applicable to people trespassing/causing a disturbance on private property.