When I was younger (like right after I came up), I used to think that everyone I saw with dreads was Jamaican. Not even "West Indian" but Jamaican. Then I realized that other Caribbean people wear dreads. But I almost passed out when I found out that there were African Americans who wear them too! LOL. :O
I knew, obviously, that there were dreadlocked Africans, but I didn't realize that Black Americans wore them. Nowadays, I think that the MAJORITY of people that I know who wear dreads are African American. I know a few Africans (born here) so "African-Americans" who wear them and a tiny handful of West Indian people who do.
It is just a hairstyle for almost all of them. In Jamaica, I don't think that you can wear dreads as a style. It is statement, a part of a lifestyle, a part of a religious belief system. I don't think that there are as many serious/strict Rastas now as when I was little but I don't live in Jamaica so I am not sure.
Also, Rastas experience discrimination in Jamaica so that also plays into it. Some people in certain professions and certain circles try to live a Rasta lifestyle- you all know the baldhead dreads.
So, now, it means nothing when I see an AA wearing locks. I figure they are just into the hairstyle and I no longer feel that we Jamaicans "own" dreads.
The take home message is that dreadlocks IS NOT EQUAL TO RASTA.