HIIIII-YAAAAAA!!!!!!!!

Thunderbolt (Peter Cannon)- Iron Fist

Only comments here are that the Peter Cannon character was originally a Charlton creation, and was only used by DC for a decade or so once rights reverted to its creator, Peter Morisi, and that Iron Fist was Marvel’s second most noteworthy martial arts after Shang Chi.

Commonalities:
I am only vaguely familiar with the Peter Cannon character, and have boned up via innuhnet research. But these two—both American guys trained in exotic mystical locations— seem to line up right up.

Differences:
Only that Iron Fist was conceived to capitalize on the kung-fu craze of the early ‘70s, whereas Thunderbolt’s provenance is based on prevailing “American guy learns ancient martial arts discipline— template common in funny books for many years by the 1960s.

Alternate histories:

TH: As a child, Peter Cannon loses his parents while on an expedition to a Tibetan monastery. He is raised therein, and eventually masters the martial arts disciplines unique to the location. Cannon returns to America and combats criminal antagonists as under the name Thunderbolt. He joins forces with the operative Steel, and the two have recently joined the non-sanctioned version of the Justice League.

IF: An American missionary couple lose their lives; their son, Daniel Rand, is raised in the hidden realm of K’un-L’un. After he masters the martial arts disciplines unique to the location, he returns to America in adulthood and combats criminal antagonists under the name Iron Fist.