For my children: I have been working on a blogspot post in my 20th Century History series and here is the research I have completed and written about but not posted. But since your comment on Multiply I am trying to pull it together. Here are notes that will help you answer the questions of your in-laws....about the early involvements of the first two decades of the 20th century. No wonder no one really is aware of these foreign entanglements that were reluctantly entered into by the Presidents...they were wars of empire, in my view.
My father and his 5 wars: (Not really wars but he had Battle Ribbons for each, and got a pension for the Spanish-American War.
Enlisted in Regular Army in 1898 at age 20. He had to have his father's signature to enlist. I have the enlistment document.
1900 Census he was at the Manila Vaccine Station. I have a copy of this census
The Phillipino natives did not want the U.S. occupation force to stay once the Spanish had been removed; the Maori fought an insurgency against the American troops.
China Boxer Rebellion
The northern peasants in an attempt to overthrow the Dynasty which had ruled China for 250 years, began a geurrilla war against the Dowager Empress and with an additional purpose of removing foreign influence in China, slaughtered both foreign Christian Missionaries and Chinese Christians as they moved toward Peking (now Beijing) they besieged the so-called Imperial City trapping Europeans and Americans in the city. Eventually the Dowager made peace with the Boxer's. An Expeditionary Force landed in early 1900 of Sailors and Marines, but failed to breach the city where the foreigners were trapped.. Regular Army including Cavalry, Artillery and Infantry left Manila and landed on the China coast, then marched toward the city fighting against roving bands of Boxer insurgents along the way. They entered and occupied Peking, rescuing the trapped foreigners. The invading force included Russians. Australian, Japanese and Europeans. Each country's forces were assigned a gate to enter what had previously been known as the Forbidden City. The Russians besieged the gate that had been assigned to the American forces, but failed after setting the gate on fire; the Americans scaled the wall and using artillery blew a new gate in the wall where Reilly's Battalion, a force from Manila entered The President did not want to enter this engagement, but there were already Army forces in the Phillapines and the Navy near Japan so with a "coalition" (sound familiar) he ordered the Army to join other countries in a "rescue" of the foreign civilians that were trapped by the Boxer Rebellion....There is an old movie about this called "44 Days in Peking". I have read Military History to find the basic information of the root of this rebellion.
The Army unit he was in returned to the Phillipines and continued to fight against the Maori Insurgency until it was pacified and the country was secured for the U.S. occupation.
My father's battalion returned to the San Francisco Presidio in 1913, where he had first served. The Army under Pershing was defending our SW borders against incursions by Mexican bandits under Pancho Villa across the border into New Mexico and Texas, and as a member of the Regular Army who had been vaccinated against tropical diseases, he was attached to this force. The Army continued into Mexico in pursuit of Pancho Villa as far as Vera Cruz....Villa was never captured but the Texas/New Mexican borders had been secured against Mexican incursions.
After the Mexican Insurrection in 1917 the U.S. entered WWI which the British had been fighting since 1914. Though my father by this time was 38 years old he remained in the Army and trained new recruits who had been drafted.
Your Hunt grandfather had joined the Army in 1917 and been at the Argonne in a long and terrible conflict where he was badly wounded in the leg, and had a partial amputation of his left leg in a battlefield hospital. He was also exposed to mustard gas which damaged his lungs and caused vision problems. He was 100% disabled. He endured two more amputations of the left leg until finally he had lost the whole leg up to his hip. He was 31 when he married your Smithson grandmother; my father married your Reeves grandmother, my mother, when she was 22 and he was 39.
My nephew Dennis has ribbons from the Spanish-American War, the China-Boxer Rebellion, the Maori Uprising, the Mexican Insurrection, and WWI.
Whether you would call each of these a "war" is perhaps a question of semantics but American military members were killed in each of these, and those who served were given a medal/ribbon for participating.