A general formula for computing the breakdown point in robustness
for the $t$th bootstrap quantile of a statistic $T_n$ is obtained. The
answer depends on $t$ and the breakdown point of $T_n$. Since the
bootstrap quantiles are vital ingredients of bootstrap confidence intervals,
the theory has implications pertaining to robustness of bootstrap confidence
intervals. For certain $L$ and $M$ estimators, a robustification of
bootstrap is suggested via the notion of Winsorization.