WASHINGTON - Veteran US senator George McGovern, reacting to President Barack Obama's decision to order a new troop surge, has called the US war in Afghanistan another Vietnam. "I am astounded at the Obama administration's decision to escalate the equally mistaken war in Afghanistan," he wrote in an op-ed article in the Washington Post on Sunday. "And as I listen to our talented young president explain why he is adding 30,000 troops -- beyond the 21,000 he had added already -- I can only think: another Vietnam," one-time Obama supporter added. "I hope I am incorrect, but history tells me otherwise," said former senator from South Dakota and Democratic presidential nominee in 1972. In a speech earlier this month, Obama announced an increase of 30,000 additional US troops to the war-torn country. McGovern also compared Obama to the late Democratic president Lyndon Johnson, who decided to escalate the US war in Vietnam. Johnson had a brilliant record in domestic affairs, but Vietnam choked his dream of a Great Society, according to McGovern. The war had become unbearable to so many Americans that Johnson, who won in a landslide in 1964, did not seek re-election four years later, the former senator wrote. "Even if we had a good case for a war in Afghanistan, we simply cannot afford to wage it," said former senator who is regarded as a World War II hero in the US. "With a 12-trillion-dollar debt and a serious economic recession, this is not a time for unnecessary wars abroad. We should bring our soldiers home before any more of them are killed or wounded -- and before our national debt explodes." Earlier this year, McGovern had urged Obama to reconsider his proposed military buildup in Afghanistan and to withdraw American forces. The new troop surge would bring the total number of US troops in Afghanistan to nearly 100,000. Apart from the presence of private security forces, there are already 100,000 US-led coalition troops in war-ravaged Afghanistan and the country has been witnessing a surge in violence. Afghan civilians have been the main victims of the long-fought war.