a policy of returning land to a country that it belonged to in the past

They are concerned about the possible irredentism of the minority in their midst. 他们担心的是自己人中的少数民族所持有的领土收复主义观点。

His program was full of irredentism and ultra-nationalism. 他提出的方案充斥着民族统一主义和极端民族主义的说辞。