who was the retired 4 star US general who said that the United States was going to go after the countries in the Arab world

The retired four-star general you’re probably thinking of is Jack Keane. He’s a retired U.S. Army general who has frequently commented on Middle East policy and Arab countries, and recent coverage also identifies him in that role.

Why this looks like him

• Jack Keane is publicly described as a retired four-star U.S. Army general.

• He has been quoted in Middle East-related commentary about U.S. actions involving Arab countries.

• If the phrase was “the United States was going to go after the countries in the Arab world,” it may be a paraphrase or a clipped quote rather than the exact wording.

Caveat

The wording in your question is a bit broad, so there’s a chance you’re referring to a different retired general, but Jack Keane is the strongest match from the available reporting.

TL;DR: Most likely Retired Gen. Jack Keane.