Does Alito getting into The Supreme Court mean we will never be able to impeach Bush? Even if we get a majority in the 2006 elections?

Any guilty decision would just bounce to The Supreme Court, and Alito would presumably help Bush stay in power and The Supreme Court would slap down any impeachment decision.

Could this be the administration's plan?

What does it matter, Clinton was impeached and still remained in power....due to the senate.

"Behind a backdrop unique in historical terms, on Saturday 19 December 1998, President William Jefferson Clinton was impeached by the United States House of Representatives, becoming only the second President in U.S. History, and the only man popularly elected as President to have been so charged.
The House voted 228 to 206 to approve proposed Article I of Impeachment (Perjury before a Federal Grand Jury), and voted 221 to 212 to approve proposed Article III of Impeachment (Obstruction of Justice).
Although the impeachment process succeeded at the level of the House of Representatives, without the Senate's confirming action in this matter, no further action was taken."