Story highlights South Korea says they're spending $1.5 billion on a "5G" network

The term is mostly a slogan for now, but the tech will come

The nation's science ministry promises new network in 2020

Cellular networks in the U.S. likely will linger behind

Is the era of 5G connectivity upon us? The government in South Korea says so, and it's sinking $1.5 billion into upgrades it says will make mobile communications there 1,000 times faster than they are today.

But not so fast. Literally, not so fast. As was the case when smartphones and other mobile devices first started having 4G slapped on them, the term 5G is as much a marketing slogan as anything else -- at this point, anyway.

And if technophiles in the United States are hoping Korea's announcement means warp-speed data connections are coming their way in the near future, they're going to be disappointed.

Regardless of the network's capabilities, any wireless carrier wanting to take advantage of them also would need costly upgrades to their systems. Users would have to purchase new devices that could access it. And even then, there's no guarantee that Netflix or similar companies would make their own data available at speeds that live up to the Korean government's tantalizing vision of an entire movie downloading in a single second.

All that said, don't count Korea out. Arguably the most wired country in the world , South Korea has led in mobile adoption since the 1990s.

"We helped fuel national growth with 2G services in the 1990s, 3G in the 2000s and 4G around 2010. Now it is time to take preemptive action to develop 5G," the nation's science ministry said. "Countries in Europe, China and the US are making aggressive efforts to develop 5G technology ... and we believe there will be fierce competition in this market in a few years."

A worldwide high of 82.7% of South Koreans use the Internet, and 78.5% of the nation's population is on smartphones. Narrow that down to 18-24 year olds and it's dangerously close to full saturation -- 97.7%.

The science ministry's plan is realistically measured. A trial 5G network is due to be rolled out in 2017, with full rollout in 2020.

The country's telecom companies, as well as native mobile companies Samsung and LG, are on board and plan to be ready to take advantage of the network, according to the government statement.

Eventually, of course, 5G will hit the U.S. and elsewhere. Remember, the difference between 3G and 4G and 5G is somewhat semantic. Significantly upgrade what we have now and you can add a number before the G.

But we'll no doubt be behind. Korea's compact geography and existing wireless infrastructure mean that upgrades can happen faster and cheaper, and will reach more of the population than in geographically spread-out countries like the United States.

The increasing number of smartphones and tablets used in the United States is already beginning to tax existing communications networks. Add an emerging wearable tech trend and connected appliances like smart thermostats, refrigerators and smoke detectors, and experts expect the U.S. will need a serious upgrade by 2020 as well.