(CNN)Before the Joint Chiefs of Staff sit down in the House of Representatives Tuesday night to listen to President Donald Trump's first State of the Union address, they likely will have had a quick and very private conversation among themselves. It goes something like this, according to two sources in the know -- they won't applaud or stand up for any political statements by the President.
How the Joint Chiefs play 'poker' during the State of the Union
The Joint Chiefs, including the chairman, Gen. Joseph Dunford, and the heads of the military services will largely remain impassive. They even make sure their facial expressions are neutral.
"It's like a poker game," says former Pentagon spokesman and CNN military and diplomatic analyst Rear Adm. John Kirby USN (ret). "You don't show anything." The heads of the services will keep checking Dunford and follow his cues. If he stands, they stand. If he applauds, they applaud. Generally the chiefs react only when a president speaks directly about the troops.
But Dunford may also be keeping his eyes on another group in the audience. The justices of the Supreme Court who also, by tradition, don't react or respond to political statements by any president. An official directly familiar with the process in recent years, says one previous Joint Chiefs Chairman regularly looked over at the Chief Justice at the time. If he and the rest of the court stood, it must be considered sufficiently politically neutral, and the military chiefs would then stand.
But as always under the Trump administration there is some uncertainty. The President likes to talk about "my generals." If he singles them out, no one is sure how and if the chiefs will react.
And just like the Cabinet, one member of the Joint Chiefs will not be present so in the event the Capitol is attacked, there is still a senior living military official.
Who will the "designated military survivor" be this year?
One Pentagon official would only say, "It's going to be the guy who isn't there."