• Demands for greater border security;
• Changes in rates and types of crimes, due to large-scale migration;
• The need to enforce newly enacted climate-related laws; and
• The need to respond to increasingly frequent natural disasters.

• Difficulties maintaining the soundness of equipment and weaponry and the health of military personnel in a changed climate;
• Loss of defense assets (for instance, military bases on low-lying islands or coasts that will need to be relocated);
• More frequent peacetime deployments, particularly for disaster relief; and
• Instability in strategically important regions, such as the Horn of Africa or the Persian Gulf.

1. Bangladesh is among the countries most severely affected by natural disasters. UN statistics illustrate the extent of these almost-annual catastrophes. Two wind storms killed 300,000 and 140,000 in 1970 and 1971, while floods affected 38 million in 1974 and 78 million in 1987.
   
2. Repeated environmental disasters have triggered migration within Bangladesh, but also into India, and these migrations have sometimes led to conflict. Rafael Reuveny found that past environmental migrations within Bangladesh and between Bangladesh and India have already triggered high-intensity conflict, mainly along ethnic lines. Generally, conflict arises as a result of competition for land, water, and jobs. But Indians are also concerned about the “Bangladeshization” of the states of Assam and Tripura. According to recent voting records, reports the Christian Science Monitor, 99 percent of the residents living on the Indian side of the India-Bangladesh border are Bangladeshi immigrants. In order to reduce and manage immigration, India has been building a 2,500-mile long, 12-foot high double fence packed with razor wire along its border.
   
3. In his article “Al Qaeda Strikes Back” in Foreign Affairs earlier this year, Bruce Riedel, a senior fellow at the Brookings Institution, warned that Bangladesh could become an important base for al Qaeda. “The Jihad Movement in Bangladesh was one of the original signatories of bin Laden’s 1998 declaration of war on the West,” he said. In 2006, “as bitter feuding between the two main political parties was increasingly ripping the country apart, there were growing indications that Bangladeshi fundamentalist groups were becoming radicalized. The political meltdown now under way in the capital, Dhaka, is creating the type of fractious environment in which al Qaeda thrives.”

Now, climate change could make the above challenges even worse. “Climate change is a threat multiplier,” Environmental Change and Security Program Director Geoff Dabelko told the Christian Science Monitor. “It’s not that it creates a whole new set of problems, it’s that it will make things that are already a problem worse.” Climate change is likely to make natural disasters more frequent and more powerful; to increase the frequency and extent of environmental migrations; and to increase grievances and the likelihood of state failure, both of which could facilitate terrorism.

Brown explains that labor migration has become an important coping strategy in drought-stricken Africa. During dry periods, young adults leave their rural homes and head for the cities, hoping to earn money for their families. Brown recommends increasing the flexibility of international migration laws to make it easier for people to travel across national borders to earn a living, but he also urges developing nations to curb the “brain drain” phenomenon by adopting incentives for workers to remain in their home countries. Moreover, he argues that wealthy developed countries, which tend to see migration as a failure of adaptation and often oppose relaxing immigration or refugee policies, should accept environmental stress as a legitimate reason for migration.