Retailers might not like to contemplate the prospect of being robbed or burglarized, but they need to think about these crimes—because criminals are. According to the ­Jewelers’ Security Alliance (JSA), jewelry retailers in the United States lost more than $85 million in 2011 because of criminals, an increase of 5.3 percent over 2010. The number of on-premises robberies soared by 19.7 percent.Despite these sobering statistics, security experts say many retailers are under-­protected. They opt for cheap alarm services and last-generation analog surveillance systems, or eschew cameras entirely. “Even though jewelers have the most risk [among retailers] in terms of being robbed or suffering bodily harm, they spend the least amount of money,” says Michael Spring, owner of PriVID Eye Security Systems in Fort Lauderdale, Fla. “Most of them just do the minimum.” Even if the c