Successful presidential second terms have been hard to come by since the end of World War II. Dwight Eisenhower signed the 1957 Civil Rights Act and dispatched federal troops to escort black students to public schools in Little Rock, Ark., but then came Sputnik and the 1958 recession. Richard Nixon resigned in the wake of Watergate early in his second term, Ronald Reagan was distracted by Iran-Contra, Bill Clinton was impeached by the House of Representatives, and George W. Bush was preoccupied by the economic collapse of 2007 and the Great Recession that followed.

So perhaps no one should be surprised that President Obama's prospects for his second term took a beating in April. Between the growing consensus that implementing Obamacare is a "train wreck" and confirmation that his administration is preventing Benghazi massacre survivors and whistle-blowers from testifying before Congress about what really happened in Libya, the outlines of a second-term collapse could take shape in the next several weeks.

A portent of trouble ahead came early in April when Time magazine's Joe Klein, normally a reliable Obama enthusiast, warned that "we are now seeing weekly examples of this administration's inability to govern." Then the Obamacare train wreck meme flashed across the headlines when Sen. Max Baucus, one of the health reform law's chief sponsors, told Health and Human Services Secretary Kathleen Sebelius that "I just see a huge train wreck coming down. You and I have discussed this many times, and I don't see any results yet." Despite Baucus' subsequent efforts to walk back his comments, the "train wreck" quickly became a staple of political conversation across the ideological and media spectrum, fueled by growing evidence that health insurance premiums for millions of Americans will soon skyrocket because of Obamacare.

The Benghazi story seemed to have fizzled out in April until Rep. Trey Gowdy, R-S.C., said during a weekend interview on Fox News that "explosive hearings" were soon to be held and suggested that they would include "eyewitness testimony" from survivors who had been kept behind closed doors by the Obama administration since Sept. 11 last year. One of those survivors was presented in-shadow Monday on Fox News' "Special Report," then Obama played possum when asked about the issue at his Tuesday news conference, claiming he was "not familiar" with it.

Obama's evasion prompted a blistering statement by House Oversight and Government Reform Committee Chairman Darrell Issa, R-Calif.: "Over the past two weeks, I have sent four letters requesting that this administration make information available about how lawyers -- who already have security clearances and are representing Benghazi whistleblowers -- can be cleared to fully hear their clients' stories. I have yet to receive any response from the Obama administration.

"Even if the president really doesn't know anything about someone wanting to come forward, his position should be that whistleblowers deserve protection and that anyone who has different information about Benghazi is free to come forward to Congress. The president's unwillingness to commit himself to protecting whistleblowers only aids those in his administration who are intimidating them."

Nothing could render Obama a lame duck quicker than an Obamacare train wreck that undermines his signal legislative victory, even as revelations by Benghazi survivors point to a colossal failure by his "leading from behind" policies overseas.