I have a healthy respect for the early Zionists, but they made at least two mistakes that resonate in our day:
1 - Yom Hashoa should be on 10 Tevet, and certainly not in Nissan.
2 - Yom Haatzmaut should be on Lag B'omer, but certainly not during Sfira.
Had they combined their new holidays with our old holidays, Jews the world-over would be able to mourn and celebrate together. And it isn't like there's no precedant for this sort of thing. Our crafty ancestors used this trick when they sabatoged Nicanor Day, and replaced it with Tannis Esther.
It's been suggested by David Williams, an expert on ancient Israel at the University of Georgia, that it was King John Hyrcanus, a descendant of the Maccabees, who shoved Nicanor Day aside in favor of Purim. Why? "Perhaps to deflect attention from Judah's victory to his own time. Or he wanted a wider celebration.''
A wider celebration. If only the early Zionists had thought along those lines.