President Donald Trump's tariffs will be "extraordinary" for business, Century Aluminum CEO Michael Bless told CNBC on Thursday.

The president signed tariffs on Thursday afternoon that slap a 25 percent levy on steel and 10 percent on aluminum. Canada and Mexico are exempt from the tariffs, which will take effect in 15 days. The U.S. will also give other nations the opportunity to justify why they shouldn't be included.

Bless told CNBC he expects Century Aluminum will be able to bring its Kentucky plant from 40 percent of capacity to 100 percent because of the tariffs.

That means 300 jobs and over a $100 million investment into the plant "to get it going and improve the technology," he said in an interview with "Power Lunch."

And he's not buying critics' arguments that the tariffs will start a trade war with other nations.

"The hysteria over this so-called trade war has reached frankly above a fevered pitch. We're not exactly sure where the trade war is coming from," Bless said.

Century Aluminum makes high purity aluminum, which is a national security issue, he said. However, the beverage industry, for example, uses mostly recycled aluminum.

"This plant at full production can make more than about 1.5 times the amount of high purity metal that our DOD and commercial aerospace sector needs," he said.

"Today most of that metal is coming from places like the Persian Gulf and from Russia and a little bit from Canada. So we'll be able to supply a good portion of that when this plant is up and running at full capacity."

And that's just one part of the equation. With his peers also opening plants and hiring, the benefits will begin to flow into other areas, Bless said.

"It's a rising tide. It will be good for the entire industry. It will help support R&D in the industry, capital investment and the further competitiveness of this critical sector," he said in an interview later Thursday on "Closing Bell."