They're mandated to raise interest rates in the event of structural inflation, not in the event of a one-time increase in prices. It would be silly if the government increasing the VAT required the fed to increase interest rates.
That's an odd, fundamentally disconnected mechanism that, I think, would have devastating impacts for Main St.
Even if the tariffs work as desired, they result in persistently higher prices. Unless you're expecting American laborers to work for less than literal Chinese robots, I guess.