"There is one more conclusion after the events in 1971-1921 that has a practical meaning for modern politicians and for all citizens. I've already said on the National Unity Day. The lack of our inner unity in face of Moscow threat in early 1920s of last century resulted in loss of independence," the head of state said at the Ivan Bohun Kyiv Military Lyceum's 'Lesson of Courage' dedicated to Kruty Heroes Memory Day on Friday. Committed political mistakes in the past the president described as "a severe lesson to all." "I demand the lesson to be learnt both by coalition and opposition, and extra parliamentary forces. Being a president I won't allow past mistakes to be repeated," the president stressed.