Former national security advisor John Bolton on Friday congratulated those who led the airstrike that killed Iranian Gen. Qassem Soleimani.

“Long in the making, this was a decisive blow against Iran's malign Quds Force activities worldwide," he tweeted of the strike ordered by President Trump that killed Soleimani and six others. "Hope this is the first step to regime change in Tehran."

IRAN THREATENS RETALIATION AFTER TRUMP-ORDERED AIRSTRIKE KILLS IRANIAN GEN. SOLEIMANI; DEMS WANT EXPLANATION

On New Year’s Eve, Bolton tweeted the attack on the U.S. embassy in Baghdad was “straight from Iran's playbook in 1979” that showed Iranian control of Shiite militia groups and not "Iraqi anti-Americanism."

“We must protect our citizens from Iranian belligerence,” he wrote.

He said Iran needs to stop arming, training and financing militia groups and shouldn't "even think about attacking American targets again."

CLICK HERE TO GET THE FOX NEWS APP

Bolton left the administration in September after Trump tweeted that he “strongly disagreed” with him on many issues.