Answer:
Senators were unsure about the implications this would bring to the United States in relation to relations with foreign countries.
Step-by-step explanation:
As you may already know, the Versailles Treaty was the peace treaty established after the First World War. This treaty allowed the winning nations to establish very heavy reprisals for the losing nations, especially Germany, which fell victim to extremely radical policies.
The nature of this treaty worried many American senators. That's because they believed that such harsh policies could damage the US's relations with losing countries and even with other countries.