Charles Ellicott Commentary Deuteronomy 30:1

"And it shall come to pass, when all these things are come upon thee, the blessing and the curse, which I have set before thee, and thou shalt call them to mind among all the nations, whither Jehovah thy God hath driven thee," — Deuteronomy 30:1 (ASV)

When all these things are come upon thee, the blessing and the curse. —The curse is still upon them, and therefore this chapter contemplates the possibility of a restoration still to come. Some would go much further than this. But this much is undeniable.

And thou shalt call them to mind. —An awakening among the people themselves must precede their restoration.