In 2008, when Barack Obama was elected to president, Governor Rick Perry discussed the possibility of Texas seceding from the United States. He was rather roundly denounced and ridiculed by the mainstream press for even speculating on the topic. In 2017, now that Donald Trump has become president, there is an actual movement for California to secede from the United States, called "Calexit."
Given the recent riots at Berkeley where violent agitators forced the university to "uninvite" Milo Yiannopoulos as a guest speaker, President Trump has threatened to cut off federal funds to the university. There is also a move to make California a "sanctuary state" in response to President Trump's plans to enforce immigration laws, again with a threat to cut off federal funding to the state (as well as any other states or cities that may declare themselves "sanctuaries").
An independent California would be no libertarian paradise. Unrestrained by the United States Constitution and Bill of Rights, the first thing to be eliminated would be any and all firearm rights. Still, if this were to go forward, the prospect for liberty as a whole look promising due to the ramifications outside of California.
The first thing to notice is the electoral balance. It is possible for Democrats to be elected to the presidency due to the 55 electoral votes provided by California, just as it is possible for Republicans to be elected due to the 34 electoral votes provided by Texas. Absent California, the Democratic Party would be at a serious loss, and not just in the electoral college. Removing California would remove two Democrat senators and a significant block of Democrat representatives. This would swing the rest of the country strongly Republican. That is not necessarily good for liberty in itself, but the eventual result could become a cascade of secession from other heavily Democrat states finding themselves in a country that has just swung strongly Republican.
Calexit would also mean that, for the second time, it is the Democratic Party leading secession. Due to the War Between the States, the concept of secession is highly tied to the idea of slavery and racism. Allegedly the parties have reversed roles on the subject of race, so if California were to lead a new wave of secession by the Democratic Party it would lead to untying the concept of secession from the racism. That would make secession a more available option for any state, whether predominantly Republican, predominantly Democrat, or fairly well mixed.
Then there is the subject of which states subsidize the others, known as red state socialism. If true, this would be an opportunity for the heavily Democrat states to stop subsidizing other states. A secession movement would actually decrease wealth transfers between states, leading to a necessity to reconstruct state budgets.
An independent California would not be beholden to the foreign policy of the United States. This would enable local solutions to the question of migration of people with Mexico. Also, in 1999, the California Public Employees' Retirement System considered divesting from Turkey for political reasons. This created opposition on the grounds that California was creating its own foreign policy contrary to United States foreign policy. Were an independent California to make such a move, there would be no similar controversy.
Ultimately this would weaken the federal government as a whole, as concessions will need to be made to prevent states from leaving when the federal government takes actions contrary to state wishes. This may be the key to finally recognizing legalized marijuana in several states, and the first step towards ending the drug war as a whole. This would also lead to greater competition between the states, especially the newly independent ones, in order to provide the best climate for people to want to live or work in those states.
That leaves just one major issue, should voters in California actually vote in favor of Calexit (not a likely prospect given the current polls). What would be the response from a Republican-led federal government? Would they allow California to leave? Would they risk looking like hypocrites given Governor Perry's musings in 2009? Would they stay true to Lincoln and attempt to stop the secession? It is difficult to determine exactly what would be the response.