There is a reason why the press — and by extension its use of television, radio and the Internet — are protected under the Constitution. It’s because it is the collective job of the press to provide vital information about national, state and local events, so that people can make informed choices and hold intelligent discourse about the important events of the day.

And the press is separate from the government, in most cases, so that it can collectively criticize the g ove r nment without fear of reprisal.

But there are times when the press itself needs to be called out. This is one of those times.

Last night, President Barack Obama gave an important speech on his decision to use executive order to make some changes to immigration law. Without wandering into the weeds about his right and privilege to do so, it is an important issue that is likely to have repercussions in this new Congress and perhaps Congresses to come.

It should have been covered on television by the major networks. It was a little more important than NBC’s reality show The Biggest Loser, or CBS’ sitcom Big Bang Theory, or ABC’s drama Grey’s Anatomy, or even Fox’s procedural Bones.

Univision showed the speech live, with analysis afterward. PBS carried the speech as well, as did the cable news networks.

But not the Big Four?

According to a White House source, the networks were approached … but not asked … and declined to give up the time for Obama’s speech. ABC did utilize its digital properties as well as include highlights of the speech on its West Coast nightly newscast; NBC and CBS also used the speech in their West Coast news broadcast.

The public nature of the airwaves means that the networks shouldn’t have to be asked whether or not they are willing to postpone their programming. It should be an absolute given. They exist to provide news and information to the public. We own the airwaves they broadcast over.

Entertainment is what they get to do when they’re not fulfilling their primary function.

So shame on the Big Four, who are ignoring the reason they are allowed to use our public airwaves in the first place.

It is not up to the networks to decide that the announcement is happening during the inconvenient “sweeps” period.

It is not up to the networks to make a decision that advertising dollars take precedence over national news, news that has the likelihood of being a major salvo in the fight for immigration reform.

It is not even up to the networks to decide that their viewers would rather watch The Big Bang Theory than engage in a knotty national security issue.

It is their job merely to offer up the time — only 17 minutes, for heaven’s sake — gracefully and with deference.