In Trump's first speech to Congress, will decorum hold?

First lady Melania Trump, accompanied by special guests, will smile from the gallery above.

The speech offers Trump an opportunity to stand before millions of viewers around the United States and the world, and try to reframe his presidency after a chaotic opening in which he's rattled world leaders, railed against leaked information, engaged in open warfare with the press and seen his signature effort to halt some immigration thwarted by the courts.

There also are big questions about how Democrats will choose to show their opposition to the president, especially if they are emboldened by the vocal Trump opponents who have turned out in force at legislators' town-hall meetings in their home districts over the past few weeks.

[...] Democrats have made a point of inviting immigrants and foreigners to attend Trump's speech as a choreographed counterpoint to his exclusionary immigration policies.

[...] GOP legislators are getting impatient for details of the president's positions on top issues such as a tax overhaul, repealing President Barack Obama's health care law and trade policy.

Senate Majority Leader Mitch McConnell, asked what he wanted to hear from Trump on Tuesday, told a Chamber of Commerce crowd in Kentucky last week: "A tweet-free, optimistic and uplifting message about where America needs to go."

While the traditions of Congress demand manners and cordiality, plenty of drama has unfolded over the years in the interplay between presidents and legislators during State of the Union speeches and other formal addresses, such as Tuesday's.