tion. The issue of secession had not been defined in the Constitution nor decided by the Judiciary; Lincoln's decisiveness, a successful fait accompli, set a precedent for later presidents to follow. Theodore Roosevelt and Franklin Roosevelt greatly expanded the presidency's authority over policy-making by using the office as a "bully pulpit" to rally national support for their initiatives Lineberry, Edwards & Wattenberg, p. 292).
The president cannot make laws, only suggest them to Congress. By the same token, by heading the Executive branch, the president controls the federal bureaucracy that administers the laws created. This has been a source of tension between the three branches of government from the beginning, for a weak president, or a willful one, can break a law by poor enactment of its provisions just as readily as by openly opposing it. Sometimes the president has done both: Andrew Jackson took on Congress by ignoring its national banking charter grants; he opposed the Supreme Court by refusing to enforce a decision granting the Cherokee nation land rights in the state of Georgia.
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