Final answer:
The Congress and Confederation's significant beneficial actions included strengthening the central government, particularly by giving Congress the ability to tax and maintain armed forces, and establishing a stable economy through the regulation of trade.
Step-by-step explanation:
The actions of Congress and the Confederation that were proven beneficial were mainly related to strengthening the central government and establishing a stable economy. Under the Articles of Confederation, there were several weaknesses that hindered the effective operation of the government, which included the lack of power to tax, regulate trade, and enforce treaties. The establishment of a new system under the U.S. Constitution rectified many of these shortcomings. Two notable actions taken were the Congress's ability to tax and maintain an army and a navy. This allowed the nation to defend itself and raise necessary funds for its operations. Moreover, Congress's power to regulate trade marked a fundamental step towards establishing a stable economy.
Prior to these developments, individual states often had conflicting trade policies, which created economic chaos and impeded the nation's ability to engage in successful foreign relations and commerce. Furthermore, a new system of federal courts was established to ensure justice, responding to the goal of establishing justice across the states. The capability to declare war, coin and borrow money, and regulate naturalization and bankruptcy were also significant actions that reinforced the stability and authority of the federal government. All these measures were essential in transforming the nation from a loose confederation of states into a more unified and effective federal republic.