Apparently not. The rate of marital breakup is spectacularly high in America--currently, over half of all first marriages end in divorce; but the rate of marital breakup in subsequent marriages is 10% higher—some 60%. As sociologists Frank Furstenberg and Andrew Cherlin point out in Divided Families, many remarried families simply don't make it through their early years together; about one fourth of all second marriages break apart within a five year period. This is a rate of marital disruption which is "significantly higher than the level among first marriages" according to Furstenberg and Cherlin.
But curiously enough, this enhanced risk of re-divorce exists only for the first five years of the remarried family's existence. At that point in time, the new family's chances of remaining together are roughly the same, or even better, than those of a family living in an intact, first-time-ever nuclear household.