This is the 1127th most frequent Turkish word.
halkının
"Of his/her/its people" or "of their people."
Halkının is used to denote possession, 'his people' in this case, referring to Atatürk and the people he led.
Atatürk, halkının güvenini kazanmış bir liderdi.
Atatürk was a leader who earned the trust of his people.
Halkının indicates possession, 'its people,' referring to the government being discussed.
Halkının refahını düşünen bir hükümet kurulmalıdır.
A government that considers the welfare of its people should be established.
Here, halkının shows a possessive relation, 'his people', tying the artist to the emotions of his community.