I find that source difficult since on some days transmission is very slow and the news sites are huge. I have been able to connect to ABCnews and Yahoo but not New York Times. So I am blissfully unaware of what is happening in the world. It's actually quite nice to contemplate voting in the upcoming elections without having to subject myself to the daily slugfest of the campaign and the yammering of the pundits. I wonder if Chinese people, even intellectuals, realize how huge the information wall is, even with the internet.
Walls work in other ways, too.
Historically, most all cities in China had walls around them for security. Apparently many cities pulled down their walls after 1949 for various reasons. In Beijing it occurred in the 1960s in order to construct the subway and the first ring road. In some places people used the bricks for other building projects. I suspect there was also a sense that city walls were old-fashioned, even feudal, so modernization included demolition just as urban renewal in the 1960s in many cities in the U.S. led to the destruction of lovely old buildings.