Given a document, find the main entity about whom the author is writing. Write the full name if mentioned in the text. Note that URLs in the text have been replaced with [Link].

Q: Rex Tillerson could be on  his  way to serving one of the shortest tenures of any Secretary of State in U.S. history.
âThere are no personnel announcements at this time â White House spokesman Sarah Huckabee Sanders said in a statement. â Secretary Tillerson  continues to lead the State Department and the entire cabinet is focused on completing this incredibly successful first year of President Trumpâs administration.â
âHeâs here.  Rex  is here â he said.
If  Tillerson  leaves in the next few months   he  would likely be viewed as one of the most underperforming secretaries of State in U.S. history with one of the shortest tenures to boot  say experts on American foreign policy.
âIt will ratify what is emerging as almost a consensus view that  Rex Tillerson  was the worst Secretary of State in modern time â said Paul Musgrave  a political science professor at the University of Massachusetts-Amherst who studies American foreign policy. âI actually think there is a good case to be made  ever.â
If  Tillerson  leaves in the next few weeks   he  will have served for roughly a year  inordinately short for a first-term Secretary of State in the modern era. The last three first-term secretaries of State â Warren Christopher  Colin Powell and Hillary Clinton â all remained in their posts for the entire term.
Aside from his short time in office   Tillerson  has little to show as accomplishments.

A: Rex Tillerson
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Q: MURDEROUS  thin-skinned and in possession of nuclear weapons  the North Korean dictator   Kim Jong Un   has one good deed to  his  name:  he  has united America and China. Max Baucus  Americaâs ambassador to Beijing until January 2017  recalls the Chinese president  Xi Jinping  privately expressing âdisgustâ at Mr Kimâs reckless pursuit of nukes and missiles to carry them to other continents. Mr Xiâs frustration with North Koreaâs hereditary despot stands out as âthe strongest statement that I have ever heard Xi makeâ  says Mr Baucus. China has never sounded as closely aligned with America when it comes to using sanctions and diplomatic pressure  in a last-ditch bid to change how Mr Kim calculates his regimeâs interests.
Unfortunately for relations between the worldâs two biggest economies  China will hate the next steps that America is likely to take on North Korea. Evan Medeiros  until 2015 the senior director for Asia in Barack Obamaâs National Security Council  says that when the Chinese accuse America of refusing to engage in talks with the regime  this is largely âposturingâ. But behind it lies a truth  that âsanctions wonât stop North Koreaâ. When battling the proliferation of the deadliest weapons  sanctions are always in a race with technology  says Mr Medeiros  now with the Eurasia Group  a consultancy. âKim Jong Un is close to grasping the brass ring. We have probably lost the race and need to think about deterrence.â This could include deploying new missiles and missile-defence systems in South Korea and Japan  and perhaps another aircraft-carrier in the region.
Still  cold-war theories of deterrence are being dusted off  with such jargon as âsecond-strike capabilityââthe certainty that a country attacked with nuclear weapons can retaliate massively. Douglas Paal  a senior Asia hand in the Reagan White House and both Bush administrations  approves of the Senate plan to place more interceptors in Alaska  in part to gain leverage over China. âWe need to layer up more missile defence. China needs to see that their second-strike capacity is really deteriorating  which hurts them.â Mr Paal  who runs the Asia programme at the Carnegie Endowment for International Peace  a think-tank  is in frequent contact with envoys of governments including Chinaâs and  recently  North Koreaâs. He concedes the need for talks with the  Kim  regime  alongside containment and deterrence  but notes that in previous negotiations  North Korea wanted an end to American defence alliances in Asia and to Americaâs troop presence in South Korea: âSo we canât get there.â
A policy of containment would not just strain relations with China as new American weapons bristled in Asia. Global non-proliferation regimes would be tested  not least because a North Korea facing crippling sanctions might see selling nuclear technology as a lifeline. Perhaps Chinaâs greatest nightmare involves Japan feeling compelled to build nuclear weapons (it could quickly develop the technology). A Chinese build-up of warheads in response could result in India and then Pakistan increasing their stockpiles. The unity fostered by  Mr Kim  may thus prove short-lived. If  he  builds the arsenal  he  wants  China and America will be sincere in their shared dismay. But if America then prepares to contain him  a whole new Sino-American stand-off may begin.

A: Kim Jong Un
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Q: Sen. John McCain (R-Ariz.) makes  his  way to a meeting in Washington about the tax bill on Dec. 1. (Photo by Bill OâLeary/The Washington Post)
 Sen. John McCain (R-Ariz.)  has been admitted to Walter Reed National Military Medical Center for recovery from the side effects of another round of treatment for brain cancer  according to  his  office.
 McCain   who missed a third straight day of Senate votes Wednesday  has been undergoing rounds of chemotherapy and radiation to treat glioblastoma  the terminal form of brain cancer he was diagnosed with in July.  McCain  has been undergoing treatments since early September at the National Institutes of Health in Bethesda  next to Walter Reed.
Two friends close to  McCain   requesting anonymity to speak about  his  condition  said there were no plans for  the senator  to resign. In a statement issued from  his  office   McCain  hopes to return âto work as soon as possible. â
Sen. John McCain (R-Ariz.)  has been diagnosed with a brain tumor. (Victoria Walker/The Washington Post)
Republican leaders expect to hold a vote early next week on the sweeping tax-cut plan that is currently in a House-Senate negotiation. The Senate version initially passed with 51 votes. If  McCain  missed the vote on final passage  Republicans would not be able to afford a single additional defection or absence to pass the legislation.
â Senator McCain  is currently receiving treatment at Walter Reed Medical Center for normal side effects of  his  ongoing cancer therapy â  his  office said in a statement. âAs ever   he  remains grateful to  his  physicians for their excellent care  and  his  friends and supporters for their encouragement and good wishes.â

A:
John McCain
****