“ In order to obtain possession and use of the land as soon as possible-and without waiting to try out the validity of the prior revocation in a separate action or actions-the Government filed a complaint to condemn whatever possessory interest respondent might be adjudicated to have. Although the Government's complaint alleged that it had revoked the lease and, in effect, that respondent had no compensable interest in the property taken, the District Court ruled that by suing for condemnation the United States had 'elected' to abandon its prior revocation. ”

“ We cannot agree that the lease permitted revocation only if the Government wanted the land for 'aviation purposes.' It is true that the preamble to the agreement states that the airfield was leased, rather than sold, because it was needed in stand-by status for naval aviation activities. ”

“ Such a strict rule against combining different causes of action would certainly be out of harmony with modern legislation and rules designed to make trials as efficient, expeditious and inexpensive as fairness will permit. ”