President Trump’s choice of H.R. McMaster for National Security Adviser sent two important messages to everyone familiar with General McMaster’s background.

First, given his groundbreaking analysis of the Vietnam War, it signals that military leaders will be taken seriously in the Trump administration. Second, given his brilliant leadership of ground forces in Operation Desert Storm and his extensive studies of Russian tactics, it tells Moscow that the United States is taking their provocations seriously.

There are plenty of provocations to consider at the moment. CNN reported over the weekend that some Pentagon officials “believe Russia is testing President Donald Trump with aggressive moves across the globe.”

One official said moves like Russia’s deployment of land-based cruise missiles, dispatching of a spy ship to the Atlantic coast of the United States, and aerial harassment of American ships in the Black Sea were tests intended to “see how the new administration will respond.”

CNN’s sources said some of these moves were clearly planned before the 2016 election and would have occurred no matter who won, but they also speculated that Russia was “taking an increasingly dim view of Trump’s likelihood of building a warmer relationship with Moscow.”

McMaster’s appointment will be taken as Trump’s response to Russia’s tests. The Russians are very well aware that he spends a good deal of his time thinking about how to defeat them. Unfortunately, he is also deeply worried that America currently lacks the manpower and equipment to win in several likely theaters of conflict, at least not without terrible losses on both sides.

The Wall Street Journal hailed McMaster, who has a doctorate in history, as “arguably the Pentagon’s foremost warrior-scholar” in a 2012 profile, which focused largely on his efforts in Afghanistan but also mentioned his tactical achievements in Desert Storm and his counterinsurgency successes after the fall of Saddam Hussein.

One of McMaster’s key counterinsurgency insights was that hunting down insurgents was less effective than working to “secure and improve life for the local population, establish reliable local government, and project determination and staying power.”

Likewise, he approached his assignment in Afghanistan by tackling local corruption and graft, realizing that foreign aid and military assistance did not help the Afghan people much if the money and equipment were stolen by corrupt officials and gangsters. While he tried to avoid direct political criticism of the Obama administration, it’s clear from the WSJ account that President Obama’s hard deadlines for troop withdrawal — win or lose — did not help McMaster in his efforts to convince the Afghans that America was a strong horse to bet on.

McMaster is noted for studying the culture of potential adversaries, as much as their battle tactics or hardware specifications. He prepared his troops for counterinsurgency in Iraq with elaborate role-playing exercises and packed them off to the Middle East with an extensive reading list that covered everything from local history to the musings of T.E. Lawrence.

He is also keen on understanding political power as a weapon of war, for both the United States and its adversaries. In a 2015 presentation for the Carnegie Council for Ethics in International Affairs, he explained that the Taliban in Afghanistan had a better understanding of weaponized politics than victorious U.S. forces, transforming themselves into a criminal gang and corrupting government institutions so that much of the Afghan system had a stake in American failure, no matter what the post-Taliban central government in Kabul desired. Iran played a similar game in post-Saddam Iraq, using Shiite militias to capture security institutions and purge Sunni Muslims from their ranks.

Even in 2012, the Wall Street Journal interviewer could see McMaster was already turning his thoughts toward future challenges, although Asia seemed a more likely theater at the time than the Russian frontier. In April 2016, Politico found McMaster “quietly overseeing a high-level government panel intended to figure out how the Army should adapt” to Russia’s stunning success at destabilizing Ukraine.

“It is clear that while our Army was engaged in Afghanistan and Iraq, Russia studied U.S. capabilities and vulnerabilities and embarked on an ambitious and largely successful modernization effort. In Ukraine, for example, the combination of unmanned aerial systems and offensive cyber and advanced electronic warfare capabilities depict a high degree of technological sophistication,” McMaster told the Senate Armed Services Committee.

Anxiety about Russian UAVs is interesting since Americans tend to assume we are the world leaders in drone warfare. In reality, Russian drones are all over the Ukraine theater, and U.S. forces may not have reliable techniques for shooting them down, having limited experience with anti-aircraft fire since World War II.

In addition to concerns about vast improvements to Russian main battle tanks and a significant edge in artillery, McMaster worried that Russia’s subversion of political institutions in Ukraine meant they have developed an advantage in precisely the sort of weaponized politics he talked about after his experiences in Iraq and Afghanistan.

In remarks published at the Small Wars Journal, McMaster warned that U.S. military thinking had grown too dependent upon relatively safe precision stand-off attacks, special-forces raids conducted with breathtaking skill, proxy forces to handle front-line combat, and the belief that almost all potential adversaries are afraid to directly engage the U.S. military. He wittily referred to these beliefs as the vampire fallacy, Zero Dark Thirty fallacy, Mutual of Omaha’s Wild Kingdom fallacy, and RSVP fallacy, respectively.

As McMaster explained, the common problem with these fallacious beliefs is that they rely excessively upon individual areas where the U.S. military is exceptionally effective, rather than folding them all together into a unified strategy that also incorporates political and economic warfare. The Russians haven’t been entirely successful at devising such a unified strategy — the Ukrainians are doing a respectable job of holding them at bay — but they’re thinking in the right direction.

Russia can only conclude that the United States is working toward devising such strategies as well, now that President Trump has named the prime mover behind last year’s “Russia New Generation Warfare Study” as National Security Adviser. Learning the lessons of military history is hard work. McMaster is the kind of thinker who can learn lessons from wars that haven’t been fought yet.