They're not going to hike rates much. They literally can't hike them enough to control inflation. You have to get interest rates ahead of inflation and if interest rates were at 8% the United States government would be bankrupt. I don't mean "ha ha" bankrupt and they have to run a deficit, I mean real bankrupt like even if every cent collected in taxes went to pay interest on the national debt there still isn't enough money. And that leaves $0 for defense or anything else. It's real bankruptcy.

It's to control inflation.

The rates that the Feds control only really impact the velocity of money in the banking system. They had a lot more impact 30 or 40 years ago when the Fed wasn't also creating trillions of dollars out of thin air annually.

However, they aren't just raising rates now, they are decreasing their balance sheet. That will arguably have a bigger impact on slowing inflation than raising rates will.

But there's not much they can do when inflation is a result of resources becoming scarce between slowing trade because of covid, and now stopping trade with Russia. The whole economy has become much less efficient.