By Elizabeth Piper LONDON (Reuters) -Britain must bolster defence investment to tackle threats not only from Russia but from China and other countries, its defence minister said on Tuesday after the new head of the nation’s army warned the country was facing its “1937 moment”. Setting out a stark view of the risks facing Britain, defence minister Ben Wallace called for more funding, a plea that was amplified by army chief Patrick Sanders with his warning that President Vladimir Putin’s Russia would probably prove an even greater threat after the war in Ukraine. “We’re not at war, but we must a…