During his childhood, he was raised by his great-grandmother Maryja Drazdouska, the wife of a Belarusian nobleman, who often spoke of the suffering the family experienced in 1918 when the communists confiscated their property.

When he was offered membership in the Communist Party of the Soviet Union and a postgraduate position at the Department of Scientific Communism, he declined.

There, he first met nationally oriented people striving for the revival of Belarusian culture and language, including Zianon Pazniak.

After starting a correspondence postgraduate program at the Institute of History of the National Academy of Sciences of Belarus, he met Belarusian historians with similar views, such as Michaś Tkačoŭ and Anatol Hrytskevich.

He also established contacts with academic circles in neighboring Lithuania, who impressed him with their patriotism and dreams of liberating their country from Soviet occupation.

[2] In 1979, already a party member, Trusaŭ participated with a group of architects and historians led by Zianon Pazniak in a successful campaign to preserve the historical center of Minsk.

[3] On Monday, October 24, he was publicly condemned at a meeting of Communist Party secretaries of the Soviet district of Minsk for his participation.

Simultaneously, the state press started a campaign against all BPF Party activists, calling them scum on the wave of perestroika.

This initiative failed, but through it, Trusaŭ established contacts with Russian democrats within the communist party – Yury Afanasyev, General Oleg Kalugin, Gleb Yakunin, and others.

He co-authored the Concept for the Transition of the Belarusian SSR to a Market Economy (autumn 1990) and several legislative projects in culture and education.

[5] Trusaŭ was one of the contributors to the official design of the Pahonia coat of arms and the white-red-white flag, the new state symbols of Belarus.

[3][7] In the latter half of 1994, after President Alexander Lukashenko came to power, Trusaŭ became one of his most active critics, accusing him of attempting to establish a dictatorship.

[3] Trusaŭ participated in the hunger strike by BNF Opposition deputies from 11 to 12 April 1995 in the Oval Hall of the parliament, protesting the president's referendum on making Russian the second state language, changing Belarus' state symbols (the white-red-white flag and the Pahonia coat of arms) to Soviet-style symbols (the current national emblem and flag of Belarus), economic integration with Russia, and the president's right to dissolve parliament.

[5] On the night between April 11 and 12, he and other protesters were forcibly removed from the parliament hall by masked military and special service personnel, beaten, loaded into a car, driven away, and then dumped on the street in central Minsk.

[8] From 13 to 14 April 1995, Trusaŭ participated in a Constitutional Court trial where the BNF Opposition accused President Lukashenko of monopolizing mass media.

Aleh knew how to remain calm and convincing in the sharpest parliamentary debates, never getting lost or agitated like some communists, maintaining a clear mind and avoiding panic where there was real danger... he was always an active defender of the Belarusian language.

[2] Together with Michaś Tkačoŭ, he initiated the creation of a new social democratic party oriented towards Belarusian national revival.

Trusaŭ and his supporters opposed this policy and soon formed a faction within the Belarusian Social Democratic Assembly aiming to maintain the party's independence.

In May 1995, Trusaŭ's faction supported the initiative of a "round table of Belarusian political parties" to remove President Alexander Lukashenko from office.

Trusaŭ believed that Vasil Bykaŭ would have been the ideal common candidate, but the lack of unity led to the democratic camp's defeat and Alexander Lukashenko's rise to power.

Trusaŭ believes that cities determine the country's fate and argues that if the president's attitude towards the Belarusian language changes, state administration will start using it within six months, and the entire society within 2 or 3 years.

Trusaŭ is skeptical of the early 20th-century spelling, known as taraškievica, used by some Belarusian-language communities today, considering it a form of showing off by the youth.