With China's weeklong National Day holiday just around the corner, there has been speculation in the Republic of Korea on whether and how much its citizens can benefit from the tourist flow from China.

The October "golden week", an annual peak of outbound travel that continuously breaks sales records of related industries at home and in the main destination countries, had been a secure source of revenues for many ROK businesses for many years.

Even last year, when ties between Beijing and Seoul had already been strained by the latter's decision to deploy the Terminal High Altitude Area Defense anti-missile system in total disregard of Beijing's security concerns and protests, tourist attractions and shopping venues in the ROK remained packed with Chinese visitors. During that one week, the ROK saw 250,000 visits by Chinese tourists, and many shopping venues registered double-digit growth in sales. So there were the claims that THAAD and souring official ties had no impact on tourist enthusiasm.

This coming National Day holiday, even more - 6 million as an industry study predicts - Chinese citizens are expected to travel abroad. But the ROK may not be among their top 10 most-favored destinations.

Obviously, this has to do with the overall relationship between the two countries, which has deteriorated inversely to the progress of THAAD deployment. Now that the entire THAAD is operational, it would be unrealistic to expect Beijing and Seoul rediscover their previous rapport any time soon. And as government-to-government ties worsen, they will inevitably spill over to undermine ties at the people-to-people level.

It does not take a government degree to stonewall things Korean. Chinese consumers can make their own decisions.

ROK businesses are correct in foreseeing they would miss China's "golden week" bus and lowering expectations. In fact, more, longer rainy days may be ahead for them as security concerns deepen the rift between Beijing and Seoul.

On the heels of its talk of embracing US "strategic assets" to counter threats from Pyongyang, the ROK military has more recently made public its intention to introduce the SM-3, or RIM-161 Standard Missile 3, a ship-based missile system known as a maritime version of THAAD. With the capability to intercept enemy missiles, even satellites, at higher altitudes, the SM-3 will further disturb the regional security balance and invite strong protests from neighboring countries. Corresponding information sharing with the US and Japan will inspire suspicion that the ROK has finally joined the US missile defense regime.

The ROK military appears fully aware of the damaging potentials. Its decision to go ahead displays an open disregard for China's security concerns, for which it will logically receive reciprocal responses. What their country loses then will certainly not be just Chinese tourist spending.