The French strategy was defensive for several reasons as
France was a democracy and a democracy does not invade other countries
France could not afford WWI scale losses
France would wait on the arrival of a big British army before starting a big offensive
Every one in France knew what happened in august/september 1914 when an offensive French strategy had resulted in more than 100000 deaths
There was NO military convention between France and CZ obliging France to start a big offensive if CZ was attacked .
AND the reason why France would fight (in 1938 and 1939 ) was moral,not strategic : the loss of CZ and Poland would not be fatal ,thus no reason to sacrifice the most valuable possessions of France : its young men .
The French would fight if THEY were attacked, but why take risks if other people,far away and of whom they knew nothing (and thus did not care about) were attacked .?
The French had also a treaty with Romania to help this country if it was attacked by the SU, or by Hungary, or by Bulgaria,but it was obvious that France could and would do nothing .
And,most important point : there was NO war, because the Czechs decided to yield to Hitler's demands :reality was that war or peace did NOT depend on Chamberlain or Daladier,but on Hitler/Benesj and that NOT Chamberlain saved peace, but Benesj .
There was a conflict between CZ and Germany: those two countries had to solve the problem . The problem was not the problem of France .Only a few people cared about the problem of the SD Germans,and most of them argued that they had the right to secede from CZ .In 1945 the Czechs said that the SD Germans had to leave, in 1938 they (and their allies ) said that they had not the right to leave .An inconsistent attitude .