Ever since Russia invaded Ukraine in 2014 and seized control of Crimea, Pentagon planners have been trying to figure out how they could cope with further land grabs by Moscow. Their greatest concern is that Russia will move on the three small Baltic states of Estonia, Latvia and Lithuania — the only former provinces of the Soviet Union that have joined the North Atlantic Treaty Organization (NATO) and that other alliance members are therefore obligated to defend. Internal Pentagon estimates suggest Russia’s military could occupy the Baltic states in 2-3 days — well before NATO could organize a coherent response.
More generally, the alliance’s entire eastern flank is vulnerable to invasion given the proximity of Russian forces and the absence of natural barriers to a quick advance (see map). In the aftermath of the Ukraine invasion, Western military planners no longer think they can predict how Russian leader Vladimir Putin might react to perceived provocations or opportunities. So the possibility of war in Europe is back on the table as a priority concern, and that means land warfare in which the U.S. Army would have to carry most of the burden.
After talking to a number of senior military officials over the past year, the picture I get is that the U.S. Army isn’t postured to stop a quick Russian thrust westward. In certain circumstances, Putin could defeat NATO forces and upset the fragile European political order put in place after the collapse of the Soviet Union. That outcome would depend on the conditions in which such a campaign unfolds, and there are dozens of factors potentially influencing the course of events. But here are the issues that come up most frequently in discussions with the Army.
Forbes: War In Europe: Why The Army Is Worried (1)