(Evan Vucci/AP Photo)

Former Wyoming senator and Bowles-Simpson deficit commission co-chairman Alan Simpson took his war of words with the head of a senior's group to a new level, defending his advice to cut Social Security as a way to tackle the long-term debt in an angry, expletive-laden letter.

Simpson called for a spirit of cooperation in the letter, but did so using colorful, occasionally coarse language. The letter to Max Richtman, the president and CEO of the National Committee to Preserve Social Security and Medicare, who criticized Simpson earlier this week in a letter published by  Politico, swings from sarcasm to bluntly expressed frustration and angry to seemingly grudging respect.

"I spent my entire public life trying to put Social Security back together and make it solvent for over 75 years.  Why don't you help me?"  Simpson wrote in the letter, obtained Friday night by ABC News.

This isn't the first letter sent by Simpson attacking a senior's group.  Earlier this week  Politico published a letter by Simpson addressed to the California Alliance for Retired Americans in which he characterized seniors as " greedy geezers."

Simpson wrote the letter to the California senior's group in response to flyers sent out by the CARA entitled: "Bowles! Simpson! Stop using the deficit as a phony excuse to gut our Social Security!"

Richtman responded to Simpson's letter to CARA, criticizing him for his "mean-spirited" tone, drawing the sharp reply from Simpson.

"Yes I could clean up my language a little, but I found sometimes that if you use gentle little terms - and I know a bit of lovely Shakespearean English - that people don't really seem to hear it," he wrote.

Simpson also lambasted seniors' groups for staying silent during the fight over the payroll tax holiday, at the same time as they encouraged their members to attack him.

"I didn't hear a peep out of your organization either - except when I got a whole ration of mail from your people - they said they were 'urged' - obviously stimulated by you (thinking I was still in the Senate) and several of your fine stalwart membership then referred to me as a 'Natzi pig f-er,'" he wrote.

Critics of the Payroll Tax Holiday passed earlier this year say the tax cut is stealing revenue from Social Security and even though it is temporary, has affected the long-term solvency of the popular social program.

Perhaps Simpson's most controversial assertion in the letter dismisses the idea that Social Security was created with the intent of providing a guaranteed retirement for seniors.

"You know damn well the system was never created as a 'retirement' - it was an 'income supplement' to take care of folks working in CCC camps who lost everything in the Great Depression," he wrote.

Social Security was created in the 1930s under President Franklin Delano Roosevelt during the Great Depression. The Trustee for Social Security at the Social Security Administration has estimated the trust fund will become run out of money in 2033.