headlines: U.S. to Send Ukraine $700 Million in Military Aid, Including Advanced Rockets
articles: That has proved to be a tricky line to walk for the president and his advisers since Mr. Putin sent his troops into Ukraine nearly 100 days ago.
  
  In his article on Tuesday, Mr. Biden described his administration’s resolve to support Ukraine in its attempts to repel Russian invaders. But Mr. Biden also offered specific assurances for Mr. Putin that the United States does not intend to provoke a wider conflict or the use of weapons of mass destruction.
  
  “We currently see no indication that Russia has intent to use nuclear weapons in Ukraine, though Russia’s occasional rhetoric to rattle the nuclear saber is itself dangerous and extremely irresponsible,” Mr. Biden wrote. “Let me be clear: Any use of nuclear weapons in this conflict on any scale would be completely unacceptable to us as well as the rest of the world and would entail severe consequences.”
  
  Mr. Biden stated bluntly in his article that he did not seek to overthrow Mr. Putin, despite his off-the-cuff remarks during a speech in Poland earlier this year, when he said the Russian president “cannot remain in power.” On Tuesday, Mr. Biden presented a different view.