It seems that everyone in Washington is talking about it except President Barack Obama: When Congress votes on the administration's request to use military force in Syria, the future of his presidency could well be on the line.
A defeat, a distinct possibility, would hobble Obama in affairs both foreign and domestic, particularly if fellow Democrats collaborate in it.
It will hurt him at a critical juncture, as he confronts not only Syria, but the nuclear activities of Iran and North Korea, another round of battles with Republicans over fiscal issues, an immigration bill, and a possibly difficult nomination fight over a new chairman of the Federal Reserve.
Using Obama's presidency as an argument as Congress ponders a resolution authorizing military action is off-limits for the administration - it would make the debate about Obama and cost the president votes from some Republicans he is counting on.
"My credibility is not on the line," Obama said at a news conference in Stockholm on Wednesday, five days after he announced he would seek congressional authorization for a strike on Syria over an Aug. 21 chemical weapons attack in that country.
"The international community's credibility is on the line. And America and Congress' credibility is on the line."
ELEPHANT IN THE ROOM
But if ever there was an "elephant" in a room, the Obama legacy is it.
A 'no' vote would be a "catastrophe" for Obama, said David Rothkopf, a former Clinton administration official who is now president of Garten Rothkopf, an international advisory firm.
"It would ratify the perception of him as a lame duck at one of the earliest points in recent presidential memory," Rothkopf said. "He would appear to be weakened and unlikely to get much done during the remainder of his term."
"I think a 'no' vote would be a huge slap at the president," said George Edwards, a presidential scholar at Texas A&M University. "It would seem to tie his hands."
It would hurt Obama even more if many Democrats - members of his own party - vote against him, which at the moment seems likely.
House of Representatives Speaker John Boehner in particular knows the consequences of being