Failed cruises made a close blockade urgent

The case for a close blockade grew out of the Western Squadron's failures in 1758. Under Anson, scurvy and victualling problems limited the force to short periods at sea, while Saunders later failed to intercept French ships entering and leaving Brest. France, losing naval strength and colonial positions, borrowed enough to keep its fleet active and sought a strategic reversal through invasion, with unrealistic hopes of Jacobite and foreign support. Brest could not feed the invading army, so troops and transports assembled around Vannes and the Morbihan. The Brest fleet would have to sail south before moving toward the Channel, which made continuous observation of the port essential.