[4] Trenin joined the Carnegie Moscow Center (which itself was set up with funding from the Nunn–Lugar Cooperative Threat Reduction) in 1994 soon after its formation in the aftermath of the collapse of the Soviet Union.

[9] Trenin was expelled from the Royal Swedish Academy of War Sciences in October 2022 "due to his active support of the unjustified and illegal Russian invasion of Ukraine in both speech and writing".

In 2001, he claimed that "a confrontation with NATO is something Russia cannot afford and should never attempt", and in the same year an American book reviewer described him as "a Russian who is ahead of his time and the vast majority of his countrymen".

According to the American neoconservative writer James Kirchick, following the reelection of Vladimir Putin in 2012 the Carnegie Moscow Center, which Trenin led, started to gradually adopt pro-Putin positions: this caused the resignation of chair of the think tank's Society and Regions Program, Nikolai Petrov [ru]; the editor-in-chief of the center's magazine, Maria Lipman; and Russian political scientist Lilia Shevtsova.

[15][16] Anatol Lieven, who used to work with Trenin, claims on the other hand that "he only represents, in a more abrupt and radical form, a shift in the Russian centrist intelligentsia that has been building up gradually for many years.