There is such a world：The Tang Dynasty survives to this day（20s of the 21st cent

There is such a world：The Tang Dynasty survives to this day（20s of the 21st century），Annexation of Tibet，Unify China，Complete national integration，Becoming a strong developing country，Constitutional monarchy制，The Tang Empire；Turkic presence in Mongolia、Buryatia and Jehol region，Constitutional monarchy，Turkic Khanate；The easternmost region of Siberia and the Kamchatka Peninsula became a Turkic-dominated Siberian Khanate.，Implementing an enlightened monarch；Korea is the Kingdom of Korea，Constitutional monarchy，It was a vassal state of the Tang Dynasty.；Japan for the United Kingdom of Japan，Constitutional monarchy，It was a vassal state of the Tang Dynasty.；Korean nationalists establish the Republic of Korea on Jeju Island，Parliamentary cabinet system，Its purpose is to recover and expel the Tang Dynasty；The United Empire of India，Unify South Asia，Federal monarchy，There are several opposition armed groups in the country，There is a border with the Tang Dynasty；West Asia, excluding the Arabian Peninsula, constitutes the Islamic State of the United Arab Republic of East，目前In civil war；Russia after World War I，The Republic，It is a capitalist bourgeois republic，Hostile to the Turks and Tang；Ukraine is a bourgeois democratic republic；The three Baltic states formed the United Baltic Republic；Myanmar constitutes the Union of Myanmar，In civil war；The three countries of the Indochina Peninsula formed the Indochina Union。Please analyze how such a world is achieved.