A testing ground for this is the debate over whether to raise the national minimum wage from $7.25 an hour to $10.10, as President Obama and many Democrats would like. Historically, raising the minimum wage has usually had no meaningful impact on hiring, regardless of what partisan advocates may claim. But this time may, uh, be different. Up till now, automation has mostly been used to streamline industrial assembly lines and other complex systems. Now, technology has gotten so cheap that a few iPads outfitted with ordering and purchasing software may be cheaper than a staff of retail clerks earning minimum wage. If the pay threshold were to rise to $10.10, it could boost overall costs at some employers by nearly 10%, according to BlackRock analysis. That may be enough to persuade a whole range of companies to replace workers with gizmos wherever possible.