these are the list of countries come under asia, imagine all of these have one common currency, is it possible what u guys think ? Afghanistan – Kabul Armenia[2] – Yerevan Azerbaijan[2] – Baku Bahrain – Manama Bangladesh – Dhaka Bhutan – Thimphu British Indian Ocean Territory[3] (overseas territory of the United Kingdom) Brunei – Bandar Seri Begawan Cambodia – Phnom Penh China, People's Republic of – Beijing China, Republic of (commonly known as Taiwan) – Taipei Christmas Island[4] (overseas territory of Australia) Cocos (Keeling) Islands[4] (overseas territory of Australia) Cyprus[2] – Nicosia Georgia[2] – Tbilisi Hong Kong (special administrative region of the People's Republic of China) India – New Delhi Indonesia – Jakarta Iran – Tehran Iraq – Baghdad Israel – Jerusalem Japan – Tokyo Jordan – Amman Kazakhstan – Astana Korea, Democratic People's Republic of (commonly known as North Korea) – Pyongyang Korea, Republic of (commonly known as South Korea) – Seoul Kuwait – Kuwait City Kyrgyzstan – Bishkek Laos – Vientiane Lebanon – Beirut Macau (special administrative region of the People's Republic of China) Malaysia – Kuala Lumpur (seat of government at Putrajaya) Maldives – Malé Mongolia – Ulaanbaatar Myanmar (formerly known as Burma) – Naypyidaw Nepal – Kathmandu Oman – Muscat Pakistan – Islamabad Palestinian territories (collectively the territories of the West Bank and the Gaza Strip) Philippines – Manila Qatar – Doha Saudi Arabia – Riyadh Singapore – Singapore[5] Sri Lanka – Sri Jayawardenepura Syria – Damascus Tajikistan – Dushanbe Thailand – Bangkok Timor-Leste (commonly known as East Timor) – Dili Turkey[2] – Ankara Turkmenistan – Ashgabat United Arab Emirates – Abu Dhabi Uzbekistan – Tashkent Vietnam – Hanoi Yemen – Sana'a
Thats never going to happen in the near or for seeable future as there are extreme wealth and extreme poverty in Asia, vast extremes, that is without mentioning junta's, dictators et al