"When I said grab your musket, I meant, look, if Hillary Clinton wins, if she wins fair and square, then the anger that a lot of Americans have towards our political system -- and she's part of that -- we gotta double down and triple down and do whatever we can to defend our freedom," he told CNN's Chris Cuomo said on "New Day."
The former Illinois congressman said he's used the phrase "grab your musket" multiple times over the past several years but never meant that Donald Trump supporters should literally reach for their firearms.
"If I wanted people to take up arms, why would I recommend people take up an antique like a musket?" Walsh asked. "That's just silly."
Walsh, who was elected with support from the tea party movement, is now a conservative talk radio host, tweeted Wednesday: "On November 8th, I'm voting for Trump. On November 9th, if Trump loses, I'm grabbing my musket. You in?"
CNN's Jake Tapper asked: "What exactly does that mean?"
"It means protesting. Participating in acts of civil disobedience. Doing what it takes to get our country back," Walsh responded.
Walsh told Cuomo that Trump supporters are angry not just at Clinton but political leaders on both sides of the aisle.
"Things in America right now are ugly and nasty," he said Friday. "We're pissed off at Republicans and Democrats."
"Even if Trump loses fair and square, Chris, the anger is not going to go anywhere," Walsh added. "I'm glad the American people are angry because we've been asleep for years."
Dan Gross, president of the Brady Campaign to Prevent Gun Violence, condemned Walsh's tweet.
"Joe Walsh's continued vile and violent rhetoric has no place in our political discussion," he said in a statement.
Walsh has made apparent threats on Twitter before. In the wake of the Dallas police officer shootings over the summer, he tweeted,
"3 Dallas Cops killed, 7 wounded. This is now war. Watch out Obama. Watch out black lives matter punks. Real America is coming after you."
At the time, he told CNN's Don Lemon that he stood by his words and that Twitter "shut me down."
"Twitter said the only way you'll open your account is if we get rid of that tweet," Walsh claimed in July.
At the time, Twitter would not comment on Walsh's claims, citing privacy and security reasons. But spokesman Nu Wexler noted a Twitter policy that says users "may not make threats of violence or promote violence, including threatening or promoting terrorism."