The White House is the official residence of the President of the United States of America.
When Robert Kelly was sworn in as president he pardoned Beast for his crimes. A mutant hate group called the Friends of Humanity learned of this and had one of their agents dress up like a mutant and attack the White House.
Puppet Master intended to have the White House torn down after he took over the world so that all power would reside only in him. However, Puppet Master was stopped by the Fantastic Four.
Kingpin intended to use the Time Dilation Accelerator to open a portal to steal the White House. However, these plans were cancelled when Kingpin lost the Time Dilation Accelerator.