"Cyber warfare" - attacking an enemy's electronic communications, including computer networks, is a growing threat, analysts have warned. Russia has provided emphatic proof of that.
Moscow sent more than troops, tanks and warplanes into Georgia when it invaded the small country earlier this month. Russian military computer hackers unleashed millions of electronic messages into critical Georgian networks, too.
As a result, computer servers handling Georgian government, communications, financial and transportation services were crippled. That created serious problems for everyone in Georgia, including civilians.
The U.S. electronic infrastructure also has been targeted. Last summer, hackers "broke into" Pentagon computers, as well as German and British networks.
U.S. countermeasures prevented the hackers from gaining much information or doing much damage.
At the time, there were accusations that the Chinese government was behind the incursions.
Both U.S. private and public-sector entities that rely heavily on computers devote an enormous amount of resources to keeping them secure.
That gives Americans a layer of protection missing in many regions of the world.
Still, Russian success in Georgia is a reminder of the need to remain vigilant - and to continue devoting the resources necessary to erecting at least a partial wall of defense against cyberwarfare.
Our nation's enemies know, perhaps more than most Americans, the havoc that can be wreaked by engaging in that form of attack.