Below we use Optimal Classification (OC) in R to plot the House’s 301-118 vote to reauthorize the FISA Amendments Act passed in 2008 and set to expire. The measure allows for the NSA to conduct a warrantless surveillance program under court supervision.
The vote is interesting from a spatial perspective in that it clearly reveals a split within the Democratic Party on national security issues and the tradeoffs involved with civil liberties. House Democrats split 74-111 in opposing passage, while all but 7 Republicans (including Ron Paul (R-TX)) supported the measure. As seen in the plot below, many of those Democrats voting “Nay” are among the more liberal members of their caucus, as would be expected given the liberal bloc of Democrats who have opposed the continuation of Bush-era national security policies under the Obama Administration, including FISA.
However, the second dimension is also important in dividing House Democrats and, to a lesser extent, House Republicans on the vote. We have previously conjectured that the second dimension has come to represent an “establishment vs. outsider” divide. For example, those MCs voting “Nay” on the August 2011 deal to raise the debt ceiling were also likely to have low second dimension scores. On this vote, the fit is very good (a PRE value of 0.73) using primarily the second dimension to classify votes on the measure. The intra-party national security divide among House Democrats appears to have some ideological organization.