Writing What You Know: The Cultural Experience
People write what they know from experience. Culture is often an integral part of this experience, including ethnicity, religion, ancestry, and local community identity. It's a given fact, however, that some people are more "cultural" than others, especially in the United States. People who aren't descended from primarily white European races typically fall into this category. The only Caucasians who can be considered cultural are the first-generation immigrants or those who are biracial. The rest of us do not have the right to write about our cultures if there is nothing special about them, and even historical significance may be controversial. However, while we may also have no right to write about other cultures, we do have the right to learn about them.
I was at one time a poet. One day in Spanish class I realized that many of the vocabulary words we had just been tasked with learning turned up in my poem, so I attempted to translate it and with my teacher's help submit it to the school's creative writing journal; it did not get published. I never got more than one in a year anyway, so it could have just not been that good; however, only the ESL (English as a Second Language) students got their works published in any language other than English, so it also could have been that Spanish was neither my nor my teacher's native language either (and so had no right to be submitting it). Being a straight-A language student does not necessarily make you fluent either, and it certainly does not make you understand the culture entirely (most Americans have that experience). As many Americans are looked down upon by people from other countries as uncultured even when they try to learn about other countries' language and/or culture, this should not come as such a surprise.
Ancestry is also difficult to write about given the many blood feuds that tend to pop up all over history. For most people, the past is the past, but others are more sensitive to it; they persist to carry it in the present and threaten to take it into the future. Most school curricula tend to ignore some of these history lessons as if knowing about them is not important; it's important to someone, however, because it happened and we all have to live with it whenever a reference comes about. We may not know our ancestors or not know them well enough to know why they did what they did, but like any member of your current family, you didn't choose them. We should not be held accountable for anyone else's actions but our own. The same goes for religious turmoil. Your relationship to a higher power is yours alone; no one else can define it for you as long as the path you're on is a peaceful one. Your religion does not choose your enemies - you do. Your religion does not define whose politics you follow - you do. That's worth writing about even if there are people who would not care to read it.
Local culture and subcultures are fair game to anyone living in it and taking part in it. Though you may not get all the details right or not know much about just how diverse a cast of characters you need to have, you have plenty of opportunity to learn. Although some people may not appreciate it and others may not think it's enough to be genuine, that should not deter you from writing about what speaks to you and including all that you see fit. While there are some areas in which you are out of your depth and may have absolutely no right to talk about, that should not discourage you from trying if you are willing to do the proper research and treat the subject matter with respect. If you still fail after doing all that, at least you gave it your best shot; in the end, the only person's opinion of your work that matters is yours.