The Army has a renewed focus on readiness, and rightly so. While the United States was engaged on two battlefields in Southwest Asia, unencumbered adversaries continued to modernize. Readiness is now the Army's number one priority, and for U.S. Army Europe (USAREUR), 2017 is the year of readiness execution. The footprint of land forces in Europe is changing to project credible deterrence and defense with postured and ready forces.As USAREUR shifts its force posture, readiness is paramount. Foundational to every readiness discussion is a shared understanding of the threat. Every Soldier needs to be able to answer the question, "Ready for what?"In USAREUR, Soldiers must be prepared to "Fight Tonight" against an adversary that has freedom of movement on interior lines of communication, significant anti-access/area-denial capabilities, and many instruments of national power to gain advantages on the battlefield. Fight Tonight is a slogan used by U.S. units in Korea, but recently the entire Army has been using it to describe its ability to respond quickly as a ready and resilient force.Establishing the Fight Tonight culture and then outlining the varying readiness postures is as important as defining the threat. Much of the Army's readiness discussion fixates on Soldiers' medical fitness and training to the Objective Training standard, both of which are obvious indicators of a unit's ability to perform its wartime missions.However, Chief of Staff of the Army Gen. Mark A. Milley acknowledges that the current aperture for readiness is much broader. He said it involves "not just training, manning, and equipping" but also "strategic deployment, rotations through contingency or training events overseas" to ensure the Army is ready to fully execute national strategic plans.INTEROPERABILITY AND CAPACITYEnabling the readiness that Milley describes will happen through USAREUR's relentless pursuit of interoperability and capacity. Interoperability in Europe is measured by the ability of multinational formations to execute secure communications, process a digital fire mission, and share a common operational picture.Capacity, for the purpose of this discussion, is the infrastructure and resources required to achieve speed of assembly. To collectively defend Europe and respond to 360-degree threats, USAREUR must have the systems and ability to muster and move formations quickly on lines of communication that cross multiple nations.For more than a decade, U.S. forces have used a force generation model that facilitated 12 or more months of preparation prior to a unit's deployment to an established theater. Because military forces in Europe will likely have only a few days of unambiguous warning in the event of a crisis, multinational formations will have to be ready to come together in a matter of days.These formations must be able to immediately plug into multinational and joint communications, fires, intelligence, and logistics systems. This requires interoperable systems for each of those functions. The absence of interoperability degrades air defense, rapid counterfire capabilities, sustainability, communications security, and the common operational picture. This degradation significantly increases the risk of casualties and mission failure.INTEROPERABILITY SOLUTIONSUSAREUR always trains with its allies and partners to ensure interoperability. All of its exercises involve multinational units. Some exercises, such as Allied Spirit, a multinational brigade decisive action training event, and Dynamic Front, a multiechelon live-fire exercise, are specifically designed to improve interoperability.Interoperability solutions can be as simple as training, as expensive as technology, or as cumbersome as legal agreements, but they need to be achieved through NATO.For secure communications, nations must issue communications security at the tactical level for their own radios. Multinational formations can then leverage tactical voice bridges to link incompatible radios regardless of waveform, frequency, or communications security.For digital fires, nations must follow the protocol of the Artillery Systems Cooperation Activities, an Army program that makes U.S. and allied nations' artillery systems compatible.Finally, to achieve a common operational picture, nations must reevaluate the restrictions placed on their mission command systems so they can federate on a secret network. Soldiers and leaders can overcome the diversity in tactics, techniques, and procedures inherent across different nations, but an inability to communicate with, see, or defend allies and partners fighting in close proximity will greatly impede mission accomplishment.BUILDING CAPACITYAn essential element for readiness in Europe is the capacity required to set the theater and move forces to the point of a crisis. USAREUR has aggressively pursued improvements in surface and air movements and infrastructure. These improvements, largely funded by the European Reassurance Initiative, ensure freedom of movement and speed of assembly and include the following benefits:• Reducing diplomatic clearance timelines to achieve a military equivalent of the Schengen Area (a group of European countries that do not require passports or customs controls at their mutual borders).• Improving railhead capability to support the loading of M1A2 Abrams system enhancement package (SEP) tanks in the Baltic states.• Standardizing the rail gauge from Poland through Estonia to eliminate transloading at the Lithuanian border.• Borrowing European Union-compliant British heavy equipment transporters to move M1A2 SEP tanks.• Bringing all USAREUR bulk fuel and ammunition hauling assets in compliance with the European Agreement Concerning the International Carriage of Dangerous Goods by Road.• Improving the forward operating site at Mihail Kogalniceanu Air Base, Romania, to provide a projection platform and forward logistics hub for sustainment capability in Eastern Europe.Systems and infrastructure to enable speed of assembly are complemented by the forward positioning of more equipment and resources. During the next three years, the U.S. Army will complete the stationing of a division's worth of equipment in five locations across Belgium, Germany, the Netherlands, and Poland as part of the Army pre-positioned stocks program.In October 2016, USAREUR received its largest Army ammunition shipment from the United States to Europe in two decades. This stock, combined with improvements and new construction of ammunition supply points in Romania and Poland, has reduced the time it takes to draw and issue ammunition and explosives for both training and contingency operations. The ammunition also provides options for leaders should the force need to transition from deterrence to defense.Cognizant that capacity is not just a military solution, USAREUR has cultivated a relationship with a German rail cargo carrier for cross-continent moves. Heavy railcars capable of hauling M1A2 SEP tanks are in short supply in Europe. Continued dialogue at both the executive and action officer levels has produced agreements to prioritize military movements and additional heavy railcars for major exercises and contingency operations.The increased readiness initiative in Europe started with a directive in the USAREUR strategic guidance to "know where your helmet is." This guidance was tested by the arrival of the 3rd Armored Brigade Combat team, 4th Infantry Division, in Europe. January 2017 marked the beginning of uninterrupted nine-month rotations of armored brigades that will provide an invaluable in-progress review of capacity and interoperability in Europe.Observer-controller trainers were poised to evaluate troops at seaports of debarkation, railheads, convoy support centers, and tactical assembly areas across Europe. As soon as the vessel ramp dropped, the 3rd Armored Brigade Combat Team was on the clock and postured to Fight Tonight. More than 37 trains, 2,827 pieces of equipment, and 3,954 people transited from Germany to meet in western Poland before onward movement to Operation Atlantic Resolve.Advantageous to this deployment was the absence of the contested environment anticipated in the next conflict, but the interoperability lessons learned and the capacity improved through exercising the system will expand USAREUR's readiness. ------------------- Lt. Gen. Ben Hodges is the commander of U.S. Army Europe. He is a graduate of the United States Military Academy. He holds a master's degree in public administration from Columbus State University, a master's degree in advanced military studies from the Command and General Staff College, and a master's degree in national security and strategic studies from the National Defense University. -------------------