Bolshevik delegation arrives in Riga in 1920 to discuss peace treaty with Bolsheviks in Polish-Soviet War

The transcript discusses the strategic use of land for protection, the inclusion of Ukrainians and White Russians in the Polish state, the mixed feelings of celebration and dissatisfaction among the people, and the eventual recognition of new boundaries by Western powers.

What does the phrase 'A wall of hope' signify in the context of the text?

Who were included for national security in the context mentioned?