– For more than a decade and a half, Larry Kudlow has been a fixture on the CNBC business news network, a pinstripe-suited conservative arguing relentlessly for tax cuts and a smaller government with tart sound bites.

Kudlow just gained considerably more influence and a more targeted audience, as President Donald Trump chose him as his top economic adviser.

On Wednesday, Kudlow said Trump called him Tuesday night and offered the job as director of the National Economic Council, which Kudlow immediately agreed to take.

The 70-year-old Kudlow will succeed Gary Cohn, a former Goldman Sachs executive who is leaving the post in a dispute over Trump's decision to impose tariffs on steel and aluminum.

Kudlow, too, had made clear his opposition to the tariffs, as did many economists. But that won't likely prove an insurmountable barrier between Kudlow and Trump, especially after the president amended his decision to say he would temporarily exempt Canada and Mexico from the tariffs and potentially other countries as well.

Kudlow has informally advised the Trump administration in the past. But moving into the White House would confer on him the official role of chief emissary of Trump's economic policies.

Friends and colleagues say Kudlow possesses two critical attributes prized by the president: He is a bluntly spoken debater and is resolutely loyal.

"He's a very sensitive man and a very logical man, which is exactly what Trump needs," said Arthur Laffer, a well-known economist and longtime friend of Kudlow.

In the Reagan administration, Kudlow worked in the White House budget office, and Laffer served on an economic policy advisory board. Both built their economic visions around the notion that tax cuts are critical for maximizing economic growth, a principle at the heart of the $1.5 trillion tax reduction Trump signed into law late last year.

In 1987, Kudlow moved to Wall Street and served as chief economist at Bear Stearns. He left that position in the early 1990s to treat an addiction to alcohol and drugs, after which Kudlow worked at Laffer's research and consulting firm.

Kudlow soon settled into the world of political and economic punditry, working at the conservative National Review magazine and ultimately becoming a host of CNBC shows beginning in 2001. He has remained a contributor to CNBC and a colleague and friend for many at the network. Indeed, among the first to report on Kudlow's possible move to the White House was Jim Cramer, the stock market guru and his former co-host on "Kudlow & Cramer." It was on CNBC that Kudlow gained a high-profile platform for explaining, defending and — at times — faulting Trump's economic agenda.

Kudlow channeled his push for lower taxes into a 2016 book he co-wrote and in which he argued that President John F. Kennedy's tax cuts had boosted economic growth. The book, "JFK and the Reagan Revolution," asserted that Reagan's 1980s tax cuts followed the same template. When Trump's own tax cuts ran into resistance over the higher budget deficits that would result, Kudlow downplayed the risks of debt. He argued on CNBC that Reagan ran even higher deficits to finance tax cuts and military spending — a formula Kudlow contends helped accelerate growth.

Laffer described Kudlow as someone who would be inclined to offer "unvarnished" advice to the president on the appropriate path for economic policy.

"And if by chance, he doesn't convince the president of something, he will be a loyal employee," Laffer said. "He stays loyal even if the decision goes against him."

Jared Bernstein, who was an economic adviser to Vice President Joe Biden during Barack Obama's presidency, said he has been debating Kudlow from the opposite side of the ideological fence for decades and still likes him. Bernstein said he has never managed to convince Kudlow that tax cuts that he has zealously championed have failed to deliver the promised growth, a view shared by many academic economists. But Kudlow understands trade, the Federal Reserve, employment, inflation and the financial markets, Bernstein said.

"And, at least on those issues, he listens," said Bern­stein, a senior fellow at the Center on Budget and Policy Priorities, a liberal think tank.

For a president who pays close attention to image and wants advisers who look the part, Kudlow seems to fit the role of high-powered aide. Customarily attired in narrow-lapelled suits, Kudlow has relied on the same New York-based tailor, Leonard Logsdail, for 26 years.

Logsdail said Kudlow still wears some of the first suits he made for him.

"He does take care of them," the tailor said.