Not six months after an impressive World Cup showing, the U.S. men's national soccer team is in distress.

Four matches since October have failed to yield a single win for the squad. As young players have been brought on to take the place of aging veterans -- a common practice at the start of a new four-year World Cup cycle -- the personality that defined this summer's national squad is nowhere to be found.

The low point came earlier this week, when Ireland stomped America 4-1 -- the worst loss for the U.S. under head coach Jurgen Klinsmann.

After the loss, players and Klinsmann himself were making light of the mental problems afflicting the team. Always an optimist, Klinsmann only had one prescription for what ails his roster:

"We have to get nastier."

Some of the struggles have been credited to a wave of new, inexperienced players Klinsmann is hoping to develop the next few years. These players have taken the places -- for now, anyway -- of older players like Clint Dempsey and Jermaine Jones, who have been excused from the team while they play in the Major League Soccer playoffs.

But questions of toughness are rampant throughout the roster. Jozy Altidore admonished himself after the loss to Ireland, saying he needs to play tougher for the team. After an impressive summer, the American soccer psyche is backsliding less than six months later.

This fall, the USMNT has managed only two ties against underdogs Ecuador and Honduras, followed by a loss to Colombia and then to the Irish.

While there's plenty of time before those poor performances take on real consequence, the team's current symptoms indicate widespread dysfunction and a loss of identity.

With Klinsmann aiming to take the USMNT even farther in the 2018 World Cup, such mental lapses aren't acceptable. The next World Cup remains far away, but there is urgent work to be done with the U.S. squad.

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