Even if Amazon CEO Jeff Bezos was serious, his surprise plan to deliver packages by flying drones probably won’t get off the ground for quite a while. That’s according to regulators and experts who have been watching the evolution of drone technology and politics from its earliest days.

“The challenge here is not the technologic capability, it’s figuring out how the law, the policy and the market all work together,” Peter W. Singer, a senior fellow at the Brookings Institute, told DNews. “There are a host of policy and legal issues to work out here; everything from de-conflicting airspace to licensing to insurance, to the threat side of this.”

Since drones were invented a few years ago, they’ve been used almost exclusively by the Pentagon and scientists. First, engineers built them to check on enemy territory, then configured to drop weapons, now to moving cargo -- such as the Marines' unmanned K-MAX helicopter ferrying supplies in Afghanistan.

BLOG: Drones To Deliver Amazon Goods To Doorsteps

The military’s deployment of drones in the past decade has paralleled their use by researchers to track endangered species, check on ripening crops or sample remote areas for environmental contaminants.

But Bezos’ announcement marks a tectonic shift. It’s the first time that a major business leader who is also outside the aerospace industry has touted drones as a purely commercial solution to the age-old question of how to deliver goods to customers quickly and accurately.

But here’s why you won’t see any hovering drone deliverers anytime soon.

The Amazon delivery drone prototype in action at the Amazon wearhouse, picking up a package.Amazon

Singer notes that small drones are currently illegal to operate in the United States, unless you have a special permit, fly them under 400 feet and are within the operator’s line of sight. Aside from universities, research institutions and a few police forces, the only commercial license for drone flight has been issued for a company surveying the Arctic.

By 2015, the Federal Aviation Administration is required by Congress to have new rules in place governing drones and their integration into commercial airspace. But even big drone supporters say 2015 is too soon to figure out all the potential hiccups.

The FAA is likely going to examine the Amazon delivery video before the company can deliver a package four miles away. Also, flying craft will have to meet some performance characteristics, according to Ben Gielow, government relations manager at the Association for Unmanned Vehicle Systems International, a drone industry trade group based in Arlington, Va.

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“There will have to be sense-and-avoid technology so you are sure it won’t crash into other airplanes, some kind of encrypted communications spectrum (and) you will have to have training for pilots. All of that stuff has not yet been established by the FAA,” Gielow said.

Then there’s the question of whether the public is ready for drones on the doorstep. Or whether Amazon will take its drones and start delivering packages somewhere else if the FAA rules take too long. Gielow noted that some European nations are already allowing small drone flights by commercial firms, including one in Switzerland that just made new high-resolution digital maps of the Matterhorn with a few drone aircraft.

“This Amazon announcement helps people understand how the technology could benefit them,” Gielow said. “Right now, folks don’t understand.”

In the meantime, the FAA soon plans to announce the location of six test sites around the country where it will be incorporating both drone and civilian aircraft, according to agency spokeswoman Alison Duquette.