The harsh tone of the discussions of the disagreements between the United States and Russia is unsettling. In response to the direct threat by the U.S. vice president – on the possibility of a response to the Russian cyberattacks against Hillary Clinton’s election campaign – the Kremlin said that it will take “measures to protect (our) interests, to hedge risks,” because Joe Biden’s “message” is “unprecedented.” It seemed that this kind of language had fallen into disuse, and it’s very unusual to convey warnings of this kind in the news media, but in today’s “cold war” between the superpowers, this bullying tone seems to be frequent.

The cyber war is not new. It has been in full swing for years and has become the battleground of the 21st century. Breaking in to your adversary’s computer system, and taking advantage of any vulnerability, is now a practice commonly carried out by all kinds of hackers. Planting a virus, installing software to reprogram the system, stealing information or changing access codes are all parts of this war.

Russia and the United States are not the only countries that have engaged in these unlawful actions; China, Israel and North Korea have also joined in. The attacks that stand out the most are that of China’s against the United States in 2015 to snoop on information on thousands of government officials; the Russian sabotage, in January of this year, of the electrical system in Ukraine, which left 225,000 people without power (as they did to Estonia in 2007); Israel’s attack in 2010 on an Iranian nuclear plant, in which some one thousand centrifuges were destroyed; and, in Europe, low-intensity Russian attacks which come to light several times a month.

What is really being talked about now is how to “respond proportionally” to the aggression against U.S. computer systems with the intention of influencing the election process. Biden did not say how or when the response to the Russian provocation might come, but he did say that the U.S. has the ability to do so; no one doubts that. The United States Cyber Command, the coordinating body for cyber-security, has 130 monitoring teams around the world that not only “look” at what potential adversaries are doing and warn of the danger, but can also “insert” programs to sabotage computer networks.

The dilemma is what retaliatory measures the U.S. should take to avoid escalating this action into a major conflict. There is no strategy, no rule book, no established protocol for responding to attacks of this type the way there are in the world of conventional warfare. Although it would, for example, be possible to respond to an act of cyber espionage with an action to block the whole Moscow electrical system, it seems inappropriate. Furthermore, the other side has the potential to respond in kind. Iran didn’t respond to the Israeli attack because it would have involved a war they were neither willing nor able to take on. The U.S. defended against the Chinese attack by making public the names of the military personnel supposedly responsible for the hack; that seems to have been enough to cut down on the number of encroachments.

Given the increasing tension with Russia, President Obama has to decide if there is a chance that his response will be a sufficient deterrent, or if it will be seen as only a gesture, in response to the expectations raised by all the publicity about an act of international political espionage, added on to earlier ones, but lacking the same impact.