For example, some have tried to argue that a war could cause a loss of language diversity. I remember how in early 2003, as the U.S. government was preparing an invasion of Iraq to overthrow that country's dictator Saddam Hussein, a professional organization for ESL teachers (TESOL, Inc.) sent a letter to the White House expressing its opposition. As I recall, one of reasons the organization gave for opposing the invasion was that it might accelerate language loss among Iraq's minority populations. How this might happen was not really explained. I remember thinking at the time that this claim was rather unconvincing, and I still do. It was pretty obvious that the TESOL leadership was simply opposed to the war, but was trying to find some way of tying their opposition to something relating to the profession they represented.
More recently, some have tried to connect language loss with climate change/global warming. According to a number of articles recently cited in a blogpost at wattsupwiththat.com, climate change could lead to reduced linguistic diversity. The basic idea seems to be that rising sea levels and other (assumed) effects of climate change will cause indigenous peoples to become "climate refugees." As they leave their traditional homelands and move to places less affected by climate change, they inevitably will be forced to assimilate into the local culture, leading them to abandon their native language for the dominant language in their new environment.
I must confess, however, that I am rather unimpressed by such an argument. A major reason is that I am skeptical of the whole notion of catastrophic climate change since it seems to me that the evidence for it (so far, at least) is less than compelling (please note that I am not denying the possibility that the average global temperature is rising or that the global climate is changing--I am merely expressing skepticism about the apocalyptic effects of climate change that have been predicted by many). Another reason is that there are a number of more likely causes for language loss, like those discussed above.
In short, it appears some are unable to resist the temptation to connect the loss of linguistic diversity to the latest political cause du jour. However, it seems to me that if we want to discourage further language loss, we first need to have accurate ideas about what is causing it in the present and about what might contribute to it in the future.
Image of "The Tower of Babel" by Peter Bruegel the Elder from Wikimedia Commons