Our government has historically supported the right to self-determination by different political or ethnic groups. However, in response to several petitions, the White House has repudiated this principle. From the Huffington Post:
A handful of "We the People" petitions calling for the government to allow various states to secede cropped up following President Obama's reelection. The White House has responded to all those which received more than 25,000 signatures within a month, the minimum required to get a response.
... [Director of the Office of Public Engagement Jon] Carson goes on to argue for a united nation based on the Founding Fathers' intentions, with the "right to change our national government through the power of the ballot."
"But they did not provide a right to walk away from it. As President Abraham Lincoln explained in his first inaugural address in 1861, 'in contemplation of universal law and of the Constitution the Union of these States is perpetual,'" Carson writes.
He adds that the Civil War "vindicated the principle that the Constitution establishes a permanent union between the States."