This bill requires the Secretary of Defense to submit annual reports to Congress detailing allied contributions to the common defense. Building on a 1985 law, Congress emphasizes the ongoing need for information regarding allied readiness and contributions to properly assess threats and resource allocation. The reports must cover all North Atlantic Treaty Organization (NATO) member countries and those participating in a NATO Membership Action Plan. Key data points include annual defense spending, contributions to military or stability operations involving U.S. forces, and any limitations placed on these contributions. Additionally, the reports will assess each country's defense industrial base, military force size, contributions to Ukraine, and foreign military sales activities. Congress expresses concern that the United States should not continue to shoulder a disproportionate share of the burden for European security, especially when some allies neglect defense spending guidelines. The bill encourages the President to seek greater acceptance of international security responsibilities and contributions from NATO members, aligning with collective defense treaties.