There is no absolute value for heroism. Heroism cannot be heroic from all points of view. Subjective worth is simply a fact of life. Philosophers can aspire to get to objective self-worth, but I am not so sure they can get up there. I could argue with you about it all day and all night; I will just say that if he had gone to Canada, that would be a heroic act, simply from a different point of view. The inability to see--and respect--others' points of view is exactly what prevents something being objectively good from all points of view. Sadly, that's the problem with objective self-worth.