A liberal patriarch of the US Democratic Party on Sunday blasted President Barack Obama's decision to send more US troops to Afghanistan, saying he was "astounded" by the escalation of the war.

"Today, I am astounded at the Obama administration's decision to escalate the equally mistaken war in Afghanistan," George McGovern, a former senator from South Dakota and Democratic nominee for president in 1972, wrote in The Washington Post.

"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," McGovern continued in an op-ed article. "I hope I am incorrect, but history tells me otherwise."

In a December 1 speech, Obama announced he would send 30,000 more US troops to Afghanistan.

McGovern compared Obama to the late Democratic president Lyndon Johnson, who decided to escalate the US war in Vietnam.

According to McGovern, Johnson had a brilliant record in domestic affairs, but Vietnam choked his dream of a Great Society.

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 recalled.

"Even if we had a good case for a war in Afghanistan, we simply cannot afford to wage it," McGovern wrote. "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."

Full McGovern op-ed at this link