Force Protection Condition Charlie — FPCON Charlie — is the second-highest security alert level used at United States military bases. It is declared when an incident has occurred, or intelligence suggests a terrorist attack is likely. It returned to the headlines in November 2026, when the Wall Street Journal reported security at RAF Mildenhall and RAF Lakenheath in Suffolk had been raised to FPCON Charlie.

What are the five FPCON levels?

The US Department of Defense uses five levels: Normal, Alpha, Bravo, Charlie and Delta. Normal is routine, Alpha follows a general threat, Bravo a more predictable one, Charlie means an attack is likely, and Delta — the highest — applies when an attack has happened nearby or is imminent. Since 11 September 2001, Bravo has been the baseline at US bases worldwide.

What changes at FPCON Charlie?

At Charlie, access is substantially restricted. The US Defense Logistics Agency says it requires a 100 per cent ID card check for everyone entering, sets continuity of operations plans in motion, and limits flights to essential operations. Roads may be closed and only mission-essential personnel admitted. It is meant to be short-term: official guidance warns prolonged use creates hardship and disrupts routine activities.

Is FPCON the same as DEFCON?

No. FPCON governs the physical security of installations against terrorist threats; DEFCON governs military readiness for conventional or nuclear attack. The two move independently: a base can sit at FPCON Delta while national DEFCON stays at peacetime level 5.

Why was it raised at RAF Mildenhall?

At least 15 US Air Force aircraft left RAF Mildenhall over two days from 10 November 2026, flight tracking cited by TWZ showed, with KC-135 tankers dispersing to Germany, Spain and Scotland and CV-22 Ospreys moving to RAF Lakenheath. The Wall Street Journal reported the moves followed an unspecified threat from Iran, which US officials have not confirmed.

Frequently asked questions

What does FPCON Charlie mean in plain English? It means commanders have intelligence suggesting a terrorist attack is likely, so bases lock down until the threat is resolved.

Who decides the FPCON level? Commanders decide: combatant commanders set the regional baseline, and local commanders can raise the level on a credible threat.

How long can FPCON Charlie last? It is designed as a short-term posture, normally lowered once the threat is investigated or passes.