A major failing of the United States Government under the Articles of Confederation was its

Responses

failure to defend Texas from being annexed by Mexico
failure to defend Texas from being annexed by Mexico

inability to allow the United States to expand
inability to allow the United States to expand

inability to regulate commerce among the states
inability to regulate commerce among the states

failure to allow the new nation to conduct foreign relations overseas
failure to allow the new nation to conduct foreign relations overseas

The correct response is: inability to regulate commerce among the states. Under the Articles of Confederation, the federal government lacked the power to regulate trade and commerce among the states, which led to economic problems such as inflation and difficulty in paying off debts after the Revolutionary War.