Senator Ted Cruz gave a rational, reasonable speech Wednesday night defining the Republican Party in 2016. It was perhaps the finest speech he had ever delivered, certainly before the biggest national audience.

He talked about freedom, less government and the Obama record. The only thing he didn’t do was endorse the Republican Party’s presidential nominee Donald Trump.

Instead, he encouraged Republicans across the country to “vote your conscience.”

That’s code for “you don’t have to vote for Trump.”

The Trump family reaction when Ted Cruz did not endorse his former opponent.

The same message Mitt Romney, John Kasich and the Bush family have been offering all week.

It was a remarkable moment in convention history, worse for the GOP than it had been for Democrats in 1980 when Ted Kennedy refused to hold hands in victory with Jimmy Carter.

When the New York delegation realized what was happening, they started chanting “endorse” during the last few minutes of Cruz’s speech. He was then booed by some delegates as he walked off the stage.

The big question is why the Trump campaign gave Cruz a prime time slot during the next to final night of the convention without a guarantee that he would endorse. Just another example of the lack of political experience by the Trump campaign.

For Cruz, this is a gamble that Trump is going to go down to an historic defeat in November, and he can point to no responsibility when he runs for president again in 2020.

It’s a risky move, and puts the Republican Party into further chaos.