Air carrier First Officer reported a traffic conflict with a helicopter while on final approach in instrument conditions; then transitioning to visual conditions. ATC instructed a turn and the flight performed a go-around to separate from the traffic; then returned for a landing.

Narrative

While on final approach; our flight was instructed to perform an immediate go-around due to conflicting tra'c crossing our approach path. This report aims to highlight the risks associated with crossing tra'c in close proximity to aircraft on final approach while fully configured for landing. Phase of Flight: Approach - Final ApproachOur flight was conducting an instrument approach to Runway 33 at MOB; descending from the final approach fix in instrument meteorological conditions and transitioning to visual meteorological conditions. I was the pilot flying. Upon switching to Tower frequency; we received landing clearance. While conducting the landing checklist; the Tower advised us of crossing traffic at our 12 o'clock and requested that we report the tra'c in sight. Both the pilot monitoring and I began scanning for the reported tra'c but were unable to visually acquire it within the first few seconds. Shortly thereafter; Tower issued an immediate instruction to 'Make an immediate left turn; climb 4;000 feet now.' At the same time; our Tra'c Collision Avoidance System (TCAS) displayed a highlighted aircraft at our altitude; approximately one mile ahead. Recognizing the potential conflict; I initiated a go-around and executed a left turn while climbing as instructed. During the maneuver; we visually identified the conflicting tra'c; a helicopter crossing our approach path. The helicopter also initiated a climb. ATC then instructed us to turn to heading 230° and climb to 3;000 feet. We complied; reconfigured the aircraft; and completed all required checklists. We were subsequently resequenced for approach; received another landing clearance; and completed an uneventful landing.Factors Contributing to the Event:- The crossing tra'c was not initially visible despite being reported by Tower.- The immediate nature of the ATC instruction required a rapid response.- The proximity of the conflicting tra'c; combined with our fully configured state for landing; added complexity to the maneuver.- The TCAS did not issue a Resolution Advisory (RA); but the tra'c was displayed as a potential conflict.Safety Concerns & Recommendations:- Enhanced coordination between Approach and Tower controllers to ensure situational awareness regarding crossing tra'c near the final approach course.- Consideration of stricter restrictions on crossing tra'c in close proximity to aircraft on final approach; especially when fully configured for landing.- Review of ATC procedures for issuing timely tra'c advisories to provide crews with better situational awareness.- Further discussion on aircraft unable to hear other military tra'c radio calls within the same airspace.While no aircraft limitations were exceeded; and a TCAS RA was not triggered; this event underscores the potential hazards of crossing tra'c near final approach. I submit this report to promote discussion and reinforce the importance of safe separation between landing aircraftand crossing traffic.