The endless discourse and analysis continues, focused on the question why the political rift between America’s left and right keeps growing wider and more pronounced, with little constructive thought about what should be done about it. The intolerance has become just plain intolerable.

We all seem to understand that fixation on the “why” with little consideration for the “what” could have serious consequences. The latest symptom of consequence is the distribution of pipe bombs to former President Barack Obama, former presidential contender Hillary Clinton, former Attorney General Eric Holder, former CIA Director John Brennan at CNN, and billionaire philanthropist and Democratic donor George Soros, a target of House Republican Campaign Committee attack ads.

There are Democrats blaming Republicans for sending the bombs. But there are Republicans blaming Democrats, too. They call it a “false flag” scenario.

The finger-pointing should stop. Investigation will reveal that somebody with a screw loose concocted the bomb plot. It’s not a party thing. Both sides must completely and unreservedly condemn such behavior without putting a hint of blame on any political friend or rival.

Meantime, we all should recognize that we are under threat of invasion. It might not seem a serious threat — not yet, anyway — but how else should we characterize a horde of several thousand people approaching our unprotected border, with no intention of stopping when they get there?

And, regardless if the marchers succeed or fail, what stops successive marches from forming?

Trump’s answer is a border wall, of course.

At the outset of the Civil War nearly 160 years ago, Robert E. Lee was torn between the factions — both the Confederacy and the Union recruited the Virginia general to lead their troops in what would be the bloodiest conflict on American soil.

Lee chose his home state of Virginia, although that’s not really the point; rather, Lee’s first objective, while rarely mentioned and even less understood or valued, became a thorn in the side of the Union forces for the initial years of the war.

Lee’s early objective, while the South was outmanned and outgunned, was to defend the home state of Virginia and the rest of the South from armed invasion by the North. Lee was aided by the natural barrier of mountains to the west, but long valleys running north-south, along with bays, estuaries and tidal basins along the east coast made Virginia a difficult region to secure from attack.

What’s more, the Civil War was a mere 50 years after the War of 1812. Worries about a European invasion remained fresh on Lee’s mind. As a child living across the Potomac during the War of 1812, Lee would have remembered the acrid smell of their White House being burned by an invading British army. There was nothing to stop a repeat — except whatever defenses Lee and Confederates could muster.

Lee secured Virginia’s borders for the same reasons that President Trump has pledged to construct the border wall with Mexico. The homeland is vulnerable without it.

But we can argue that another day.

In both instances — the sending of mail bombs and the march against a sovereign border — we are behaving foolishly by exposing our weaknesses to the world. We are like siblings striving to destroy each other while true enemies watch with glee at the destruction.

We have lost sight of the fact that people and nations exist who do not care for the United States and desire greatly to see America fail. And they don’t particularly care which party is in power when it happens.