The migrants' path through Mexico is a map of violence and extortion and is studded with sites of atrocities like the 2010 massacre of 72 migrants near the northeastern town of San Fernando by the Zetas drug cartel.
Diplomatic tensions have also increased at the other end of the migrants' path.
Be it a treacherous journey through the Mediterranean on flimsy boats or dodging border patrols, teargas canisters and water cannons in a desperate trek across the Balkans, the migrants' path to Europe is not just a threat to physical integrity.
Many argue that they already have appealing candidates for 2016, from Mr Romney's running-mate Paul Ryan, a deer-hunter with an iPod full of rock anthems, to the Florida senator Marco Rubio, a child of immigrants with reformist ideas about offering migrants paths into legal employment.So much for the comforting excuses.
The conservative opponents are thrilled that they have blocked efforts to give migrants a path to legalisation and potential citizenship.
The Senate failed to pass a comprehensive immigration reform bill on April 7, which would have tightened border controls while offering most undocumented migrants a path to citizenship.
Neoclassical theory, for instance, predicts that migrants take the path of migratory movement from the least developed countries to the richest countries.
Remitting large amounts in order to enjoy high marginal returns to remittances would distort the migrant's consumption path excessively (insufficient consumption in period 1) compared to the balance offered by savings (point S).
More recently Mr Bush has started saying that migrants need a path to some kind of legal status, "not necessarily" involving the status of citizen.
Before Obama spoke, activists had warned the dozens of people who'd crammed into the office of Hermandad Mexicana, an immigrant advocacy group based a few miles from the Las Vegas strip, that Obama's move was a big but incomplete step, that their struggle would continue until all law-abiding undocumented migrants had a path to citizenship.
