As the U.S. economy takes hit after hit, President Obama is taking heat for his 10-day fun-in-the-sun vacation at Martha's Vineyard that began Thursday. From the left: Colbert I. King, op-ed writer for The Washington Post, observed: "Mr. President, Martha's Vineyard is the last place in the world you should visit. ... You simply don't have time to take time off from America." From the right: Mike Murphy, a Republican strategist, told the Daily Beast that Obama is "acting like the rich guys he wants to raise taxes on." From The Donald: Obama "takes more vacations than any human being...