Time and again since Japan emerged as a global economic force, its financial leaders have hatched plans to translate their influence into investment-banking clout. Time and again, they've failed.

The retreat sounded last month by Nomura Holdings Inc. marks just the latest overseas flop, prompting current and former executives, as well as analysts, to question if they can ever make it in international capital markets.

"Japan is a manufacturing powerhouse but a financial lightweight," says David Threadgold, a Keefe, Bruyette & Woods analyst in Tokyo who has followed banks in Japan for more than three decades.