Which is considered a watch dog of the performance of the government?

the recent bombing of the uss cole is one of many incidents of terrorism directed against the united states. more than 40 percent of the world’s terrorism is directed against u.s. targets.   pursue the alleged perpetrators through the criminal justice system, and still others would beef up intelligence capabilities. to deal with potential attacks involving weapons of mass destruction, some analysts advocate extending the reach of law enforcement agencies or spending more on domestic preparedness programs; others would encourage a policy of u.s. military restraint overseas to attempt to reduce the motivation for terrorist attacks on u.s. targets.

china unilaterally claims the entire south china sea as sovereign territory, then builds artificial islands to bolster its claim. it suddenly activates an air defense identification zone over the east china sea, and threatens to down any aircraft that does not report its position. it builds roads into indian territory, then redraws the maps to show that it is actually chinese territory. the people's republic under president xi jinping is quickly becoming the bully of asia.

the answer is use of support  

the second significant cause of the great migration was the desire of black southerners to escape segregation, known euphemistically as jim crow. rural african american southerners believed that segregation - and racism and prejudice against blacks - was significantly less intense in the north.