Washington (CNN) Sen. Ted Cruz -- a man who once warned that the country would "plunge into the abyss" under a Donald Trump presidency -- is now offering gushing praise for the President, calling him a much-needed "flash-bang grenade" who has upended the status quo in Washington for the better.

"The fact that his first year as commander in chief disoriented and distressed members of the media and political establishment is not a bug but a feature," the Texas Republican wrote of Trump for Time magazine's list of the 100 most influential people of 2018 that was published Thursday.

The Texas Republican touts Trump's achievements as passing tax reform, bringing jobs back to the US and taking a "strong stand" against North Korea. Any bitterness Cruz might hold from the personal attacks and vitriol he and Trump exchanged during the 2016 primary was absent from his glowing profile of his party's leader.

During the contentious GOP primary , however, Cruz called Trump "utterly amoral," a "serial philanderer" and a "narcissist at a level I don't think this country's ever seen."

Trump, meanwhile, nicknamed Cruz "Lyin' Ted," pushed an obscure conspiracy theory that Cruz's father was involved in JFK's assassination and threatened to "spill the beans" about Cruz's wife.

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