The correct response is: "So what?" Regardless of the regulated pollutant, the rule will generate large scale returns.
But there are signs now of a large-scale return to the air.
Though there are good reasons to be optimistic about Somalia's future, it is also important to recognise the challenges that currently make large-scale return impractical.
The refugees and their descendants now number around four million, but the Geneva document would give Israel the right to block any large-scale return.
But it remains unclear whether an Iraqi government dominated by religious Shiites will be eager to embrace the large-scale return of these young men of fighting age.
It is hard to prove anything, but there are cases where large-scale return migration has coincided with (and perhaps boosted) political and economic change.
Russia could also turn up pressure on Kyrgyzstan to evict American forces that support operations in Afghanistan and could block any large-scale return to Uzbekistan, which expelled the Americans in 2005.
Abbas, himself a 1948 refugee, privately argued against the large-scale return of refugees in a meeting in March 2009: "On numbers of refugees, it is illogical to ask Israel to take 5 million, or indeed 1 million," he told officials.
"Combined with key international events – such as the large-scale return of asylum seekers to Afghanistan following the fall of the Taliban and the decrease in Sri Lankan arrivals with the hiatus in the conflict [there] – the policy did discourage boat journeys.
Nasser Yassin, director of research at the American University of Beirut's Issam Fares Institute for Public Policy and International Affairs, thinks a large-scale return deal is unlikely in the near future.
Over the next several decades -- primarily as a consequence of the inclusion movement and the ascension of high stakes testing -- we have witnessed a dramatic reduction in specialized, intensive instructional programs for students with LD, and a corresponding large-scale return of students with LD and other types of disabilities to regular classes.
