That doesn’t seem like a very accurate summary of the article you’ve linked to. That article actually says right there in the title that the ambassador, April Glaspie, has gotten a “bum rap”, and goes on to explain that Ambassador Glaspie merely correctly stated U.S. policy, which was that the United States did not have an opinion on exactly where the Iraqi-Kuwaiti border should be and only desired that any dispute be settled peacefully and in accordance with international law (and not by, say, invading the whole country and subsequently annexing the entire place as a province of Iraq). The article also states that the Iraqis weren’t looking for any kind of American permission to invade Kuwait, didn’t actually interpret the ambassador’s statement that way, and invaded for their own reasons.
The article does cast some blame on a member of Congress, Lee Hamilton, for essentially forcing the the Assistant Secretary of State for the Near East to publicly declare that the United States did not have any formal treaty obligation to defend Kuwait. That was of course perfectly true, but not necessarily the sort of thing you want to publicly declare on the eve of another country invading Kuwait. As the subsequent Persian Gulf War showed, just because the United States was not formally obligated to defend the sovereignty of Kuwait did not mean that the United States could not choose to defend the sovereignty of Kuwait as a matter of American national interest, including an American national interest in upholding the post-World War II international order in which countries are not supposed to go around invading and annexing each other anymore. (The Iraqis may not have been looking for American permission to invade Kuwait, but Saddam Hussein did clearly miscalculate in underestimating what the actual response of the United States would be to such an invasion.)