Also, while everyone can see the need for repair and renovation of existing infrastructure, this requires far more decentralized spending than mega projects, and may be harder to initiate and finance from the centre. Put differently, high-return infrastructure investment is a good idea but may be hard to implement on a large scale for most advanced country governments.
To the extent that such debt fuelled spending creates a self-fulfilling virtuous cycle of confidence and activity, it can be a bridge to sustainable growth.