Looking at this, I think I regret not catching hold of an attorney and suing Amtrak for hate crime/racial discrimination when a Diner staff on #21 last year told me "You should not come into the Diner again. Are you a terrorist?" and then followed up with "just kidding". I could have presented a good case that he said what he said because of my skin color and made some good money from Amtrak, either from lawsuit or as out-of-court settlement. Alas, I am not one of those sue-happy people.
I have no reason to doubt this happened as stated. However, even if you were willing to sue that doesn't mean your lawsuit would actually go anywhere. A lawyer (or firm) would need to believe in your case enough to cover the costs until judgement or settlement. Depending on the complexity of the case and duration of the lawsuit these costs could far exceed what any one of us could afford on our own. Presumably there were witnesses to this event but finding them and convincing them to participate in your lawsuit might not be easy or beneficial if they're not already willing to help and capable of presenting a clear and concise explanation of the incident in question. Bringing a generic he-said/she-said dispute to court is unlikely to be resolved in your favor. In some cases it could even backfire if the defendant is able to provide evidence and witnesses claiming the lawsuit was motivated by fraud or some sort of vendetta.
That being said, there's certainly nothing wrong with approaching a lawyer's office and seeing what they have to say about it. You might have to talk to a few different firms before you find one that is familiar with situations similar to yours. Then let them decide if it makes sense to move forward or not. To some people maybe it's mostly about the money, but to others it's more about pushing lazy bureaucracies to educate their employees on what makes for an acceptable joke and what makes for an unacceptable attack on their passengers. If some stranger randomly and suddenly accused me of being some sort of terrorist out of the blue I would not be happy about that, joking or not. If I were indirectly paying the salary of my clueless harasser through by conducting business with their employer I'd be pissed. On the other hand if another employee had immediately corrected and/or apologized for their ignorant coworker's remarks I would not be as motivated about the necessity for initiating legal consequences. That's where Amtrak presumably failed in my view. Nobody can completely prevent stupid remarks in a company of Amtrak's size, but they can absolutely foster an environment where coworkers are willing and able to correct mistakes before they become public relations problems of this magnitude.
I've actually contributed to many larger legal causes, most of which involved lawsuits that never requested (and never resulted in) any monetary settlement beyond documented legal fees.
Personally I've only been directly involved in a handful of legally actionable events.
In all cases I decided against taking action.
In most cases this was due to three simple facts...
1. Many people who flout the law have little or nothing to lose that is of any specific value to them.
2. Our legal system has surprising difficulty punishing those who are directly responsible.
3. Even when the right person or entity is punished for the right reasons the benefit of continuing to flout the law often outweighs the repercussions.
On the other hand, as blind and helpless as our legal system can be, it's still better than what many countries provide for those who have been the target or victim of crime or abuse. Making use of our justice system is still dependent upon our needs and abilities, and nothing is ever guaranteed in the legal realm, but that's still far better than having nothing at all.