Joe Walsh once was known as a loudmouth politician from Illinois.

Now he’s just a former loudmouth pol, who has entered the discussion about health care reform in a most undignified and ironic manner.

Late-night TV comedian Jimmy Kimmel went on the air Monday night and revealed that his newborn son was born with a heart ailment. Nurses detected a problem with the baby, a renowned cardiac surgeon was summoned and he repaired the infant’s heart.

Kimmel gave a heartfelt and tearful testimony that saluted the medical staff at the hospital where little Billy was born — and argued on behalf of efforts to guarantee health insurance for all Americans.

Then came Joe Walsh, who tweeted, “Sorry Jimmy Kimmel: your sad story doesn’t obligate me or anybody else to pay for somebody else’s health care.”

Social media erupted with outrage at Walsh’s insensitive reaction. Walsh is a former Republican lawmaker who once popped off with remarks about Black Lives Matter and President Barack Obama that some folks had interpreted as a threat. Walsh, who’s now a TEA Party activist and a talk-radio host (imagine that), was defeated for re-election.

There’s more — of course.

Walsh also once was caught failing to pay child support for his own children; he reportedly owed about $117,000 in support payments.

Tsk, tsk, tsk …

For this clown to interject himself into a heartwarming story involving an entertainment personality and his family speaks pretty graphically about this individual’s profound lack of character and compassion.

The word “hypocrite” also comes to mind.