More than six weeks after they blocked roads into three of Hong Kong’s most prominent districts, pro-democracy protesters haven’t given up. But despite their staying power and political success, the students are understandably frustrated.

In their sole negotiating meeting three weeks ago, local authorities rejected revised rules for the election of Hong Kong’s chief executive that exclude candidates not backed by Beijing.

Consequently, student leaders are discussing whether to travel to the mainland in an attempt to “have a direct dialogue with Beijing officials,” as student leader Alex Chow said recently. Chow and his fellow students are hoping to impress not just President Xi Jinping but also the leaders he is hosting this week at an Asia-Pacific summit – including President Obama.

Most likely the pro-democracy students won’t be allowed anywhere near the summit – or Beijing, for that matter.

But President Obama, who pledged in September to step up support for pro-democracy movements, even when it “causes friction,” ought to take a cue. Though he can’t oblige President Xi to listen to the students, he can make clear that the U.S. backs their call for genuinely free elections.

Remarkably, the president and his administration so far have failed to do that.

On the contrary: A statement issued by the U.S. Consulate in Hong Kong in September declared that “we do not take sides in the discussion of Hong Kong’s political development, nor do we support any particular individuals or groups involved in it.”

It is important to speak up even when doing so is uncomfortable – and even when it may not bring immediate results. Silence will do nothing for U.S.-China relations – only embolden those who favor a crackdown in Hong Kong.