Obama has just recently initiated a program to hire vets to clean up and fix the parks. So why doesn't he in his role as Commander in Chief initiate a major clean up and reconstruction of the interstate system and claim it as an act of National Defense, thereby allowing him to use funds from the Defense Department?
After all one of the major justifications for the the interstate system was Eisenhower's insistence that the United States needed better lines of internal communication in case of an attack on the homeland. Obama as Commander of all the Armed forces is tasked specifically in protecting the homeland.It is would be well within his purview to fix the aging infrastructure as a matter of national security. He could hire millions of unemployed using Defense Department funds freed up by the winding down of the wars in Iraq and Afghanistan. With the help and expertise of the Army Corps of Engineers the country could begin the massive restoration of the roads and bridges that make up these lines of communication.
There is quite a substantial amount of unallocated funds in the defense budget that may be moved around at the President's discretion. It could pressure congress to jump on board.