All that talk about the Joe Biden “firewall” in South Carolina showing cracks, fissures, weakness now appears to have been, well, just talk.

It held firm as the former vice president of the United States cruised to a smashing victory today in the Democratic Party presidential primary.

More than half of the state’s primary voters are African American. Biden depended on that base of support to carry him to victory. Sen. Bernie Sanders’ early wins in New Hampshire and Nevada and his strong showing in Iowa cast doubt on whether that firewall would withstand the pressure being applied.

Commentators described African American voters as “pragmatic,” that candidates’ strength becomes a factor in how voters would cast their ballots.

Then came an apparently pivotal endorsement from U.S. Rep. James Clyburn, a South Carolina political icon and the most powerful African American in Congress.

So, the firewall — if that’s what we’ll call it — got plenty of reinforcement.

It held the former VP in good stead. Now it is time to see whether a similar firewall forms in other states with substantial numbers of African American voters. You know, states such as, let’s see … Texas!

The primary caravan is on its way here.