A cyclist passes one of Dublin's many unfinished and bankrupt private housing developments. (AP photo/Shawn Pogatchnik)

The countries of the European Union, particularly those belonging to the less powerful "periphery," have faced a common political challenge: getting their citizens to go along with austerity measures. Putting aside the economic wisdom of those policies, the politics can be tricky. In a number of those countries, most notably Greece, outrage against austerity measures has exacerbated public protests and even accelerated the rise of political extremism, particularly on the far right. It's bad news for the health of those countries today and for their long-term prospects.

One country, though, has been relatively successful in imposing austerity without sparking a damaging backlash: Ireland. The Economist explains that Ireland's history of emigration -- when times are hard, citizens move abroad -- has helped ease the politics.

For all the anger, emigration provides an economic and social safety-valve. It had reduced Ireland's unemployment rate and the burden on the state's overstretched finances. And emigration may help to explain a puzzle of Irish politics: why the Irish people, for all their history of political revolt against British rule, have been less rebellious against austerity than, say, the Greeks.

This, in part, has allowed the Irish government to negotiate more favorable bail-out terms and to more easily implement economic reforms. The Economist suggests the country could have "a good claim to being a model of adjustment through austerity and structural reform." Again, that's putting aside the economic question of whether those are the right policies, but it seems to have allowed Ireland to more easily navigate the political aspects of austerity.

Of course, even if emigration helps in the short term, it could be risky in the long term. Generally speaking, a national population needs to grow, not shrink, for an economy to expand over the long term. In long-time economic powerhouses countries such as Germany and Japan, declining birthrates are seen as a sign of coming economic decline and, as a result, possible political turmoil. Even if emigration helps in the short term -- fewer unemployed, less social unrest, more effective politics --  its demographic effects could undo all that good in the long term.

This poses sort of a chicken-and-egg problem for Ireland. Does the emigration "release valve" provide short-term space for the country to solve its long-term problems, hopefully in time for it to renew demographic growth? Or does the population outflow just create yet another long-term issue? It's probably a combination of both, but the Irish example here is one that other E.U. periphery countries might consider -- whether to adopt or to avoid.