Perhaps also, consider the action of Spain. To quote a source:
Spain expelled the United States' ambassador and recalled its diplomats from Washington.
U.S. declared war on Spain...
Albeit, technically an expulsion which, per a source is described as, to quote:
Under Article 9 of the Vienna Convention on Diplomatic Relations, a receiving state may "at any time and without having to explain its decision" declare any member of a diplomatic staff persona non grata. A person so declared is considered unacceptable and is usually recalled to his or her home nation. If not recalled, the receiving state "may refuse to recognize the person concerned as a member of the mission". A person can be declared a persona non grata before that person even enters the country.
In diplomacy, a persona non grata (Latin: "person not welcome", plural: personae non gratae) is a status sometimes applied by a host country to foreign diplomats to remove their protection by diplomatic immunity from arrest and other normal kinds of prosecution.
So, expulsion is a stronger action discouraging either entry into a country or precipitating a hasty recall from said country, as a consequence of the removal of the protective umbrella of diplomatic immunity (especially with regard to possible arrest and prosecution).
If the intent of the question is when a Western country ever applied a diplomatic boot to America, then Spain in 1898 likely qualifies.