text: Chapter 1
  Overview
  Adaptive adversaries and enemies will contest United States joint forces across all
  domains— air, sea, land, space and cyberspace. Enemies are likely to employ anti-
  access strategies to prevent friendly force ability to project and sustain combat power
  into a region, and area denial strategies to constrain our nation’s freedom of action
  within the region. Assured access— the unhindered national use of the global
  commons and selected sovereign territory, waters, airspace and cyberspace, is
  achieved by projecting all the elements of national power. Often the United States
  requires operational access— the ability to project military force into an operational
  area with sufficient freedom of action to accomplish the mission. Operational access
  is the desired condition that the United States seeks to maintain in areas of strategic
  importance, to achieve assured access. Army forces, as part of joint forces project
  forces into an operational area and conduct operations to defeat enemy anti-access
  and area denial capabilities and establish security conditions and control of territory
  to pressure freedom of movement and action for follow-on operations or deny that
  area’s use to the enemy. Forcible entry operations are complex and always involve
  taking prudent risk to gain a position of relative advantage over the enemy. Equally
  critical is the transition between phases of the operation. This chapter discusses
  forcible entryoperations and in particular the application of vertical envelopmentas a
  tactical maneuver conducted by airborne or air assault forces to seize, retain, and
  exploit the initiative.
  SECTION I – FORCIBLE ENTRY OPERATIONS
  1-1. United States forces gain access to sovereign spaces through invitation (humanitarian relief),
  negotiations (basing rights), coercion (peacemaking operations under United Nation charter) or through
  force. The joint force’s ability to project power and influence is challenged by proliferated anti-access
  weaponswithincreasingrange, diversity,densityand sophisticationinthe handsofbothstateand nonstate
  actors who are devising innovative approaches to contest joint forces in all domains. This evolving threat
  necessitates the development of comprehensive joint force solutions for gaining and maintaining
  operationalaccess.(RefertoJP 3-18formoreinformation.)
  1-2. The composite of the conditions, circumstances, and influences that make up an operational
  environment affects the employment of capabilities and impacts the decisions of commanders. The
  operational environment of the access force includes all enemy, adversarial, friendly, and neutral systems
  across the range of militaryoperations; it includes an understanding of the physical environment, the state
  of governance, technology, local resources, and the culture of the local population. (Refer to JP 2-01.3 for
  moreinformation.)
  1-3. Forcible entry is the seizing and holding of a military lodgment in the face of armed opposition (JP
  3-18). A lodgmentis a designated area in a hostile or potentiallyhostile operationalarea that, whenseized
  and held, makes the continuous landing of troops and materiel possible and provides maneuver space for
  subsequent operations (JP 3-18). A forcible entryoperation is conducted to gain entry into the territoryof
  an enemy by seizing a lodgment as rapidly as possible to enable the conduct of follow-on operations or
  conduct a singular operation. The operations must be designed to provide maneuver space for subsequent
  operations. This section addresses the principles and operational application of joint forcible entry