Trailing the Pack = leaving behind?

Context:

Scientists Fear WFIRST Will Be Trailing the Pack

The 1990s were a decade of glory for U.S.
astronomers, including the discovery of dark
energy and planets outside the solar system.
But the instrument that they say would keep
them at the forefront—even its name refl ects
that aspiration—may be too costly for the U.S.
government to build.
Last August, a National Academies panel
charged with ranking the priorities of U.S.
astronomers for the next decade identifi ed
the Wide-Field Infrared Survey Telescope
(WFIRST) as its top choice in the category
of space observatories. The panel recom-
mended that NASA launch the $1.6 billion
mission by 2020 as the best way to advance
the study of dark energy and the search for
new extrasolar planets.
But hopes of realizing that goal appear to
be fading. The ballooning cost of the James
Webb Space Telescope (JWST), and the
resulting delays in its launch, have all but
guaranteed that the space agency will not be
able to deliver WFIRST by 2025, much less
the end of the decade. And NASA has rejected
a backup plan that would have given it a 20%
stake in a similar European dark energy mis-
sion. That decision, announced last week,
leaves U.S. astronomers with the prospect of
being marginalized in the next decade.