Uncle Academic: "Why Constitutionalists should welcome Senator Specter's defection to the Democratic Party"

It is true that

• The Republican Party line (at least yesterday) is that Specter's jump is "a purely Pennsylvania matter."  
  
• (A telling exception: Senator Olympia Snow (R, Maine) says the defection is devastating for the Republican Party.)
• Chris Matthews of CNBC (who toyed with running as a Democrat against Spector for 2010) disparages Spector's character as "disloyal."  [See also here and here.]  
  
• (Actually, this and the reaction previously cited are the opposite sides of the same coin.)
• And according to Next Right, "Early reaction (Daily Kos, Glenn Greenwald, The New Republic, MyDD, Open Left) suggests Senator Arlen Specter has somehow managed to join a political Party that dislikes him even more than Republicans did."
• Specter is not a progressive.  (Many of us might have looked forward to a progressive victory over Toomey, the right-winger who was going to win the Republican primary.) 

But constitutionalists of whatever stripe should welcome Specter's switch.  

They should resolve to hold his feet to the fire for the excellent declarations he has made about steps he will take to reverse the erosion of balance of power among the three branches of governments that has happened since 9/11 in "The Need to Roll Back Presidential Power Grabs" (New York Review of Books, 14 May 09) -- here or here.

Also, 

Additional angles, also worth a look:

• Dan Gilgoff, "Christian Conservatives Will Cheer Specter Defection, but Toomey Is a Long Shot" (28 Apr 09).
• Katherine Q. Seelye, "Reaction to Specter’s Move Is Divided by Party" (NYT, 29 Apr 09) -- on reactions within Pennsylvania.
• "Reaction to Pennsylvania Sen. Arlen Specter plans to switch to the Democratic Party" (AP, 28 Apr 09) -- some national political figures react.
• BarbinMD, "More Conservative Reaction On the Specter Switch" (Daily Kos, 29 Apr 09).  Concluding line:  "Please note that the delusional ones are considered to be voices of the Republican Party."
• John Grooms, "Specter Defection Jerks the Monkey's Chain" (The Clog, 29 Apr 09).
• James O'Toole and Timothy McNulty, "Specter stuns Senate by switching parties:  Says daunting poll results swayed him" (Pittsburgh Post-Gazette, 29 Apr 09) -- on (among other things) possible effects on candidates in the Pennsylvania primary.
• Ken Klukowsi and Ken Blackwell, "Specter's Switch means the Future of the Supreme Court Hangs In the Balance" (The Fox Forum, 20 Apr 09) -- conservative columnists pine for Supreme Court to give Coleman victory over Franken.
• "Longtime GOP Sen. Arlen Specter becomes Democrat" (CNN, 28 Apr 09) -- some useful history.
• Christopher Keating, "Simmons: Arlen Specter's Switch Has Impact on CT 2010 Race" (courant,com, 29 Apr 09) -- Simmons, likely 2010 opponent to Senator Dodds (D, CN),  floats some hopes.
• Michael O'Brien, "Inhofe: Specter switch foreshadows 2010 GOP landslide" (The Hill's Blog Briefing Room, 29 Apr 09) -- More Republicans adopt Obama campaign slogan "Hope."