Last night, during the U.S. Men's National Team's latest dismal performance, a 4-0 thrashing by Costa Rica, a commentator on beIN Sports said the team lacked an identity. This has been a common refrain for all five years of Klinsmann's tenure, and is also shorthand for saying they're bad. Nothing has changed, or really gotten better at all, and that's the problem. Taking zero points from the first two Hex round matches, which has only ever previously happened to Trinidad & Tobago, have resulted in calls for Klinsmann's job, and for good reason.
Managers are often sacked without an eye to timing or a plan for what comes next. This is why now is the right time to do it.
The U.S. doesn't play another Hex match until the end of March. The four-month gap is the biggest in the U.S.'s schedule for the remainder of the Hex. It gives the U.S. Soccer Federation the most time to do a bit of a search and find a candidate who can improve on the team's basics, although reports are that former U.S. coach and current LA Galaxy coach Bruce Arena is the leading candidate to replace Klinsmann. This four-month period also gives the new coach time to prepare. He can work with some players during the winter training camp in a low-pressure environment before having to perform in meaningful games.
The new coach wouldn't be coming into a hopeless situation, either. This roster should be able to make up four points in the table in eight games. It won't be easy and the margin for error has largely closed, but it's eminently doable.
However, if the USSF waits until things get really dire, whoever they hire will be coming into a much tougher situation. If the U.S. only takes, say, one point from their next two games and then Klinsmann is fired after those games in a panic move, the new manager will have six matches to get something like 15 points, including an away game at Azteca. At that point, firing Klinsmann would accomplish little, a classic case of too little, too late. The goal of firing Klinsmann should be to get a new manager in who can succeed, not to punish Klinsmann for poor performances.
Either fire Klinsmann now when a new manager has a little breathing room and time to put in their changes, or ride Klinsmann out until the bitter end. It is now or never.