Hahahaa, sorry, I did not mean to bash you. Also I respond late because I do not visit the site often as I am very busy and thus short on time.
I just wanted to point out the confusion and logical fallacy in your statement. There are a lot of implicit premise in your statement which leaves a lot of question unanswered which can only be surmised with readers' own assumptions filled in. The most glaring question is the following. You said "大華府地區的富貴社區仍然沒有地鐵". The fact that "潛在罪犯隻在自己的東南部社區相互對射,他們並不樂意花上一個小時,坐地鐵來到西部或北部去打槍或搶劫。" could be due to that it is not worthwhile to rob a not-so-rich neighbourhood with one hour's travel. That leaves the great possibility that had the subway been constructed through the richer area, it would have been more than worth the travel, greatly aided by the convenience of the subway, to rob the rich. Hence, your conclusion "這種擔憂被證實是不必要的" does not stand logically, and has not "被證實".
I agree with 清漪園 on this point. Gun violence in poor neighborhood usually happen between criminal gangs who have no reason to travel to remote suburbans to fight.
however, the lack of public transportation does prevent people from finding jobs, which partly explains why so many people from those communities are on welfare.
Your deduction process is not clear. You acknowledged "大華府地區的富貴社區仍然沒有地鐵,連道路都是對開的彎曲小路". How does the fact that the subway is not built lead to the conclusion "這種擔憂被證實是不必要的"? Can you explain your logic?
大華府地區也曾經是一個種族隔離的城市,有色居民多住東部與南部,白人亞裔則多住西部與北部。這裏的老住戶告訴我,70年代修地鐵時,Georgetown, Great Falls 等富裕的白人區出於雅美兄所提到的同樣的擔心,拒絕讓地鐵穿行。但是,這種擔憂被證實是不必要的,潛在罪犯隻在自己的東南部社區相互對射,他們並不樂意花上一個小時,坐地鐵來到西部或北部去打槍或搶劫。在西部和北部的罪犯,多是住在當地的居民。