Speaking at a rally in Greensboro, N.C., Republican presidential candidate Donald Trump told the crowd why his campaign took media credentials from Washington Post reporters. (Reuters)

Jose DelReal is one of a small team of people who cover Donald Trump's presidential campaign for The Washington Post. On Wednesday, he was in Milwaukee to cover an appearance by Trump running mate Mike Pence. DelReal was barred from covering the event as a reporter, in keeping with Trump's six-week-old ban on The Washington Post. DelReal then tried to enter the event as a citizen. He was told he could not enter with a cell phone despite the fact that other people were not held to that same standard. He put his phone and computer in the car and again tried to enter. He was refused — again — and patted down. “I don’t want you here. You have to go,” the security official told him.

That should scare the hell out of you.

It's easy to let this whole episode fall into a partisan trap. "He deserved it!" Trump allies will argue. "Reporters at mainstream outlets are biased against Trump! Maybe if you told the truth sometimes, he would let you in!"

Righto.

Here's the thing: If we start banning citizens — like Jose or me or Michelle Malkin or Rachel Maddow or anyone else — from attending public events for one of the two people who will be our next president, we are sliding down a slippery slope to a future reality that is a very, very bad thing for our country.

To be clear: Jose was trying to cover the event for an established news organization. Although I think it is beyond ridiculous that The Post is banned from covering Trump, I suppose he retains the ability to decide who will be granted special access to his events. (The news media typically have to wait in a much smaller line to get into the event and don't have to compete for seating.)

But Jose then went and waited in line like everyone else. No special treatment. Yet he was clearly treated differently from other people seeking to attend the rally. A pat-down? Really?

This is not a partisan issue. This is about how we treat each other. And we are increasingly turning one against the other — a me-vs.-you dynamic that is destructive not just for our politics but also for our country.

Whether you hate the media (most of you) or love us (very few of you), you should acknowledge the necessity of having an entity that is seeking to hold our politicians and public figures accountable, to fact-check their claims, trying to explain why and how they are seeking the nation's highest office.

That is not a good or a bad thing — it is a necessary thing for a healthy democracy. For those of you who disagree, consider the alternative. That's a much scarier future — for all of us.

The Post's Margaret Sullivan explores what might have led Donald Trump to revoke the newspaper's media credentials. (Peter Stevenson/The Washington Post)