Washington (CNN)The unraveling security situation in Yemen -- the same country President Barack Obama cited as a model for his fight against ISIS -- could throw the President's counterterror message into question ahead of Tuesday's State of the Union address. In Sanaa on Tuesday, the presidential palace was overrun by Shiite Houthi rebels, a situation the country's minister of information described as the "completion of a coup." That's a problem for the United States, which has relied on the government in Yemen as an ally in  battling the al Qaeda affiliate that's based there. A power vacuum could benefit al Qaeda in the Arabian Peninsula (AQAP), the terrorist offshoot that U.S. officials consider the most dangerous branch of the global jihadi network.
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President Obama had cited Yemen as a success story in fight against terrorists
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The United States had been working with Yemen's government
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Houthi rebels took over the presidential palace in Yemen, official says
"It is consistent with the approach I outlined earlier this year:  to use force against anyone who threatens @placeholder's core interests, but to mobilize partners wherever possible to address broader challenges to international order."