"When the treaty was in force, Attila again sent envoys to the eastern Romans demanding the fugitives. They received the envoys, honoured them with many gifts, and sent them away saying they had no fugitives. Again, he sent others, and, when they had been enriched, he sent a third embassy and a fourth after it. For the barbarian, mindful of the Romans’ liberality, which they showed out of caution lest the treaty be broken, sent to them those of his retinue whom he wished to benefit, inventing new reasons and discovering new pretexts. The Romans heeded his bidding and obeyed whatever their master issued. They were not only wary of starting a war with Attila, but they were afraid also of the Parthians [i.e. Sasanids] who were preparing for hostilities, the Vandals who were harrying the coastal regions, the Isaurians whose banditry was reviving, the Saracens who were ravaging the eastern parts of their dominions, and the Ethiopian tribes who were in the process of uniting. Therefore, having been humbled by Attila, they paid him court while they tried to organise themselves to face the other peoples by collecting their forces and appointing generals." - Priscus of Panium, fr. 10 (Blockley): Attila exploits Roman weakness (443/7)

While the East was occupied by wars with Persia, Saracens, Ethiopia, Vandal coastal raids and Isaurian revolt, how was it that the West was weakened so much by Alaric, Geiseric, Attila etc. to be at the point of no return in the 5th century?