We may be, if push comes to shove, be able to forgo ties with the U.S.

如果情况危急，我们也许可以放弃与美国的关系。

They can do this if push comes to shove.

如果迫在眉睫，他们可以做到这一点。

If push comes to shove, you can always sell the car.

【push】实在没有办法的时候，你总还可以把车卖掉。

We can let in a few to buff up the numbers, if push comes to shove.

如果迫在眉睫，我们可以让一些人来提高数字。

So Catherine is saying if push comes to shove they can buff up their numbers by letting in gatecrashers.

所以凯瑟琳说， 如果到了紧要关头， 他们可以通过让闯入者进来来增加他们的人数。