Core Viewpoint - The article highlights a rare display of the UK's nuclear deterrent capabilities through Prime Minister Starmer's inspection of the Vanguard-class submarine "Vanguard," which recently returned from over 200 days of patrol, while also revealing issues related to the aging submarines [1][3]. Summary by Sections - **Inspection of Submarine** - Prime Minister Starmer's visit to the "Vanguard" submarine marks the first inspection by a UK Prime Minister in over a decade [2]. - **Nuclear Deterrent Display** - The visit is interpreted as a signal to Moscow, reaffirming the UK's status as a nuclear power, despite the aging issues of its submarines [3]. - **Aging Submarine Issues** - The Royal Navy's Vanguard-class submarines, which entered service between 1993 and 1999, are facing significant maintenance challenges due to aging, leading to extended patrol durations from an initial maximum of 80 days to an average of 163 days over the past three years [5]. - **Operational Readiness** - Due to the aging fleet, only two Vanguard-class submarines have been operational, necessitating the extension of deployment times to ensure at least one submarine is always on standby [5]. - **Future Submarine Development** - The UK government has been working on the Dreadnought-class submarines to replace the aging Vanguard-class, but delays in the project mean that completion is not expected for at least another 15 years [6].