Cruiser as well as the scaled-down CGN-42 (Virginia-class cruiser hull) alternative, some of the requirements were transferred to the DDG-47, and the class was eventually re-designated as guided missile cruisers, CG-47, to reflect the additional flagship capabilities added due to cancellation of the strike cruisers, which originally were expected act as flagships for the smaller destroyers. Ships of the class from CG-52 onwards were equipped with the Mk 41 vertical launch system. As the Aegis combat system and the additional cruiser roles added substantial weight to the Spruance-derived hull, the design had limited growth potential in terms of weight and power margin. In the 1980s, a design study known as Cruiser Baseline (CGBL) was created to accommodate the capabilities of CG-52 (Mk 41-equipped ships of the Ticonderoga class) on a hull with design and construction techniques matching the DDG-51 () for improved survivability and weight allowances. Proposed early retirement Due to Budget Control Act of 2011 requirements to cut the Defense Budget for FY2013 and subsequent years, plans were being considered to decommission some of the Ticonderoga-class cruisers. For the U.S. Defense 2013 Budget Proposal, the U.S. Navy was to decommission seven cruisers early in fiscal years 2013 and 2014. Because of these retirements, the U.S. Navy was expected to fall short of its requirement for 94 missile defense cruisers and destroyers beginning in FY 2025 and continuing past the end of the 30-year planning period. While this was a new requirement as of 2011, and the U.S. Navy has historically never had so many large missile-armed surface combatants, the relative success of the Aegis ballistic missile defense system has shifted this national security requirement onto the U.S. Navy. Critics had charged that the early retirement of these cruisers would leave the Navy's ship fleet too small for the nation's defense tasks as the U.S. enacts a policy of "pivot" to the Western Pacific, a predominantly maritime theater. The U.S. House of Representatives passed a budget bill to require that these cruisers instead be refitted to handle the missile defense role. By October 2012, the U.S. Navy had decided not to retire four of the cruisers early in order to maintain the size of the fleet. Four Ticonderoga-class cruisers, plus 21 Arleigh Burke-class destroyers, are scheduled to be equipped for anti-ballistic missile and anti-satellite operations. In March 2019, the Navy proposed decommissioning the six oldest ships; Bunker Hill, Mobile Bay,