In my perspective, this scene was written to reflect two things:
1. The stereotypical American Dream: Many people entering the United States come with the mindset that they can do whatever they want because there is opportunity everywhere. America is the land of the free and it will definitely be much better than their homeland.
2. How the American Dream has become more difficult to achieve due to the government: due to cases such as 9/11 where America has been under attack, authorities have made it much harder for immigrants to prosper in our country. They are discriminated (see also: Indians) against by authorities, passer-byers, neighbors, etc. for no apparent reason.
I feel as though the author could have expanded upon this particular issue much more than he did. Through my scholarly research in looking for ways in which people are affected due to instances like 9/11, the vast majority of information I found had to do with the ways immigrants were affected. Since it appears as though Little Brother is in direct connection with the attack on 9/11, it only seems fit for him to include the large factor of immigrants/immigration.
See original contribution pertaining to Doctorow's writing and immigration statistics.
