During WWII, Britain in particular tried various tactics to get the US on their side; but what about WWI? The U.S at that time really didn't have much of a standing army and its only action on the world stage was fighting the Spanish. Did the allies of WWI even want the U.S to field an army? Was there any trepidation on their part as to whether the U.S could fight effectively?
^ These answers I've given should be pertinent
During WWII, Britain in particular tried various tactics to get the US on their side; but what about WWI?
While there are some allegations in the case of WWI that sinking like the Lusitania were supposed to convince the United States to enter the war, and it seems that this was a hope held by Churchill, it was more a hope that Unrestricted Submarine Warfare in general would convince the Americans to enter the fray. In this respect, there's some similarity to sinking in WWII like the Athenia and the Reuben James, but that's about it. There was also considerable materiel crossing the Atlantic in both wars, but in the case of WWI this was from private American companies/firms, while in WWII it was under the auspices of the US Government, via the Lend-Lease Acts.
Did the allies of WWI even want the U.S to field an army? Was there any trepidation on their part as to whether the U.S could fight effectively?
By the time of American entry into the war, it was certainly hoped that American manpower and industry would tip the balance, but this proved to be something of a double edged sword. The bulk of American artillery, tanks, aircraft and weapons came from French production, putting some strain on the French Army in 1918, while the performance of the AEF was lacklustre to say the least. The Marines took heavy casualties at Belleau Wood, while the victory at St. Mihiel was against poor quality German troops, assigned to hold the sector which was considered a quiet front, who were in the process of evacuating the Salient when the Americans attacked. The major American effort, the Meuse-Argonne Offensive, was placed in jeopardy, in turn placing Foch's Bataille General in jeopardy, due to poor American infantry tactics (better suited to 1914-16 than 1918), the ad hoc American logistical organization that produced traffic jams and led to hunger and exposure to the autumn weather because rations and warm clothing couldn't reach the front. As combat experience and adoption of Franco-British set-piece attack methods improved their performance, the AEF got back on track, but it came at a high price: 110 000 American soldiers died in WWI, the overwhelming majority from July 1918 onwards, 50 000 from combat and 60 000 from Influenza. The Meuse Argonne Offensive remains the bloodiest battle in American military history.